diff --git a/lib/utils.lua b/lib/utils.lua
index 551e1b0..5645e01 100644
--- a/lib/utils.lua
+++ b/lib/utils.lua
@@ -196,6 +196,12 @@ function utils.invoke(instance, name, ...) -- {{{
     end
 end -- }}}
 
+function utils.cb(fn) -- {{{
+    return function()
+        return fn
+    end
+end -- }}}
+
 function utils.extract(list, comp, transform, ...) -- {{{
     -- from moses.lua
     -- extracts value from a list
@@ -225,13 +231,33 @@ function utils.setfield(f, v, t) -- {{{
     end
 end -- }}}
 
-function utils.getfield(f, t) -- {{{
+function utils.getfield(f, t, isSafe) -- {{{
     -- FROM: https://www.lua.org/pil/14.1.html
+    -- TODO: add 'tryGet()' — safe get that *doesn't* cause other errors during startup
+
     local v = t or _G -- start with the table of globals
+    local res = nil
     for w in string.gmatch(f, "[%w_]+") do
-        v = v[w]
+
+        if type(v) ~= 'table' then
+            return v -- if v isn't table, return immediately
+        end
+
+        v = v[w]     -- lookup next val
+
+        if v ~= nil then
+            res = v  -- only update safe result if v not null
+        end
+
+        log.d('utils.getfield — key "word"',w)
+        log.d('utils.getfield — "v" is:', v)
+        log.d('utils.getfield — "res" is:', res)
+    end
+    if isSafe then          -- return the last non-nil value found
+        if v ~= nil then return v
+        else return res end
+    else return v           -- return the last value found regardless
     end
-    return v
 end -- }}}
 
 function utils.max(t, transform) -- {{{
@@ -252,6 +278,8 @@ function utils.boolToNum(value) -- {{{
 end -- }}}
 
 function utils.toBool(val) -- {{{
+    if type(val) == 'boolean' then return val end
+    log.d(val)
     local TRUE = {
         ['1'] = true,
         ['t'] = true,
@@ -409,14 +437,6 @@ function utils.zip(a, b) -- {{{
     return rv
 end -- }}}
 
--- function utils.zip(a, b)
--- 	local rv = {}
---   for k,v in pairs(a) do
---     rv[v] = b[k]
---   end
--- 	return rv
--- end
-
 function utils.copyShallow(orig) -- {{{
     -- FROM: https://github.com/XavierCHN/go/blob/master/game/go/scripts/vscripts/utils/table.lua
     local orig_type = type(orig)
@@ -527,7 +547,7 @@ function utils.levenshteinDistance(str1, str2) -- {{{
                     (char1[i] == char2[j] and 0 or 1))
         end
     end
-    return distance[len1][len2] / #str2 -- note 
+    return distance[len1][len2] / #str2 -- note
 end -- }}}
 
 function flattenDict(tbl) -- {{{
diff --git a/stackline/configmanager.lua b/stackline/configmanager.lua
index d7ec887..077e166 100644
--- a/stackline/configmanager.lua
+++ b/stackline/configmanager.lua
@@ -1,53 +1,24 @@
 -- https://github.com/erento/lua-schema-validation
-local v = require 'stackline.lib.valid'
-local o = v.optional
 local log = hs.logger.new('sline.conf')
-log.setLogLevel('debug')
+log.setLogLevel('info')
 log.i("Loading module")
 
+local M = {}
+
+-- Validators & type lookup
+local v = require 'stackline.lib.valid'
+local o = v.optional
 local is_color = v.is_table { -- {{{
     white = o(v.is_number()),
-    red = o(v.is_number()),
+    red   = o(v.is_number()),
     green = o(v.is_number()),
-    blue = o(v.is_number()),
+    blue  = o(v.is_number()),
     alpha = o(v.is_number()),
 } -- }}}
-
-local cb = function(fn) -- {{{
-    return function()
-        return fn
-    end
-end -- }}}
-
-local function unknownType(v) -- {{{
+local function unknownTypeValidator(v) -- {{{
     log.i("Not validating: ", schemaType)
     return true
 end -- }}}
-
-local M = {}
-
-function M:getPathSchema(path) -- {{{
-    local _type = u.getfield(path, self.schema) -- lookup type in schema
-    if not _type then
-        return false
-    end
-    local validator = self.types[_type]()
-    return _type, validator
-end -- }}}
-
-function M.generateValidator(schemaType) -- {{{
-    if type(schemaType) == 'table' then
-        local children = u.map(schemaType, M.generateValidator)
-        log.d('validator children:\n', hs.inspect(children))
-        return v.is_table(children)
-    else
-        log.i('schemaType:', schemaType)
-        return
-            M.types[schemaType] and M.types[schemaType]() -- returns a fn to be called with value to validate
-            or unknownType -- unknown types are assumed-valid
-    end
-end -- }}}
-
 M.types = { -- {{{
     ['string'] = {
         validator = v.is_string,
@@ -78,7 +49,6 @@ M.types = { -- {{{
         coerce = u.identity,
     },
 } -- }}}
-
 M.schema = { -- {{{
     paths = {
       getStackIdxs        = 'string',
@@ -111,6 +81,28 @@ M.schema = { -- {{{
     },
 } -- }}}
 
+function M:getPathSchema(path) -- {{{
+    local _type = u.getfield(path, self.schema) -- lookup type in schema
+    if not _type then
+        return false
+    end
+    local validator = self.types[_type].validator()
+    return _type, validator
+end -- }}}
+function M.generateValidator(schemaType) -- {{{
+    if type(schemaType) == 'table' then
+        local children = u.map(schemaType, M.generateValidator)
+        log.d('validator children:\n', hs.inspect(children))
+        return v.is_table(children)
+    else
+        log.i('schemaType:', schemaType)
+        return
+            M.types[schemaType] and M.types[schemaType].validator() -- returns a fn to be called with value to validate
+            or unknownTypeValidator -- unknown types are assumed-valid
+    end
+end -- }}}
+
+-- Config manager
 function M:init(conf) -- {{{
     log.i('Initializing configmanager…')
     self:validate(conf)
@@ -138,9 +130,13 @@ function M:validate(conf) -- {{{
         self.autosuggestions = u.keys(u.flatten(self.conf))
     else
         local invalidKeys = table.concat(u.keys(u.flatten(err)), ", ")
-        hs.notify.show('Invalid stackline config!',
-            'invalid keys:' .. invalidKeys,
-            'Please refer to the default conf file.')
+        hs.notify.new(nil, {
+            title = 'Invalid stackline config!',
+            subTitle =  'invalid keys:' .. invalidKeys,
+            informativeText = 'Please refer to the default conf file.',
+            withdrawAfter = 10
+        }):send()
+
         log.e('Invalid stackline config:\n', hs.inspect(err))
     end
 
@@ -159,7 +155,16 @@ function M:autosuggest(path) -- {{{
     end
     table.sort(scores, asc)
     log.d(hs.inspect(scores))
-    return scores[1][2], scores[2][2]                       -- return the best 2 matches
+
+    local result1, result2 = scores[1][2], scores[2][2]           -- return the best 2 matches
+
+    hs.notify.new(nil, {
+        title = 'Did you mean?',
+        subTitle =  string.format('"%s"', result1),
+        informativeText = string.format('"%s" is not a default stackline config path', path),
+        withdrawAfter = 10
+    }):send()
+
 end -- }}}
 
 function M:getOrSet(path, val) -- {{{
@@ -173,10 +178,13 @@ end -- }}}
 function M:get(path) -- {{{
     -- @path is a dot-separated string (e.g., 'appearance.color')
     -- return full config if no path provided
-    if path == nil then
-        return self.conf
+    if path == nil then return self.conf end
+
+    local ok, val = pcall(u.getfield, path, self.conf)
+
+    if ok then return val
+    else self:autosuggest(path)
     end
-    return u.getfield(path, self.conf)
 end -- }}}
 
 function M:set(path, val) -- {{{
@@ -185,15 +193,18 @@ function M:set(path, val) -- {{{
        non-existent path segments will be set to an empty table ]]
 
     local _type, validator = self:getPathSchema(path) -- lookup type in schema
+    val = self.types[_type].coerce(val)               -- coerce val to correct type when possible
 
     if not _type then
-        hs.notify.show('Did you mean?', self:autosuggest(path), string.format(
-            '"%s" is not a default stackline config path', path))
+        self:autosuggest(path)
     else
-        local isValid, err = validator(val) -- validate val is appropriate type
+        local isValid, err = validator(val)           -- validate val is appropriate type
         if isValid then
             log.d('Setting', path, 'to', val)
             u.setfield(path, val, self.conf)
+
+            local onChange = u.getfield(path, self.events, true).onChange
+            if type(onChange) == 'function' then onChange() end
         else
             log.e(hs.inspect(err))
         end
diff --git a/stackline/stackline.lua b/stackline/stackline.lua
index d43707c..5a7d378 100644
--- a/stackline/stackline.lua
+++ b/stackline/stackline.lua
@@ -1,9 +1,9 @@
 require("hs.ipc")
 u = require 'stackline.lib.utils'
 
-local wf  = hs.window.filter -- just an alias
-local u   = require 'stackline.lib.utils'
-local cb  = u.invoke
+local wf = hs.window.filter -- just an alias
+local u = require 'stackline.lib.utils'
+local cb = u.invoke
 local log = hs.logger.new('stackline')
 log.setLogLevel('debug')
 log.i("Loading module")
@@ -12,18 +12,33 @@ stackline = {}
 stackline.config = require 'stackline.stackline.configManager'
 stackline.window = require 'stackline.stackline.window'
 
-stackline.focusedScreen = nil
+function stackline.init(userConfig) -- {{{
+    log.i('starting stackline')
+
+    stackline.config:init(          -- init config with default conf + user overrides
+        table.merge(require 'stackline.conf', userConfig)
+    )
+
+    stackline.manager = require('stackline.stackline.stackmanager'):init()
+
+    stackline.manager:update() -- always update window state on start
+
+    if stackline.config:get('features.clickToFocus') then
+        hs.alert.show('clickTracker has started')
+        log.i('FEAT: ClickTracker starting')
+        stackline.clickTracker:start()
+    end
+end -- }}}
 
-stackline.wf = wf.new():setOverrideFilter{ -- {{{
+stackline.wf = wf.new():setOverrideFilter{
     visible = true, -- (i.e. not hidden and not minimized)
     fullscreen = false,
     currentSpace = true,
     allowRoles = 'AXStandardWindow',
-} -- }}}
+}
 
 local click = hs.eventtap.event.types['leftMouseDown'] -- print hs.eventtap.event.types to see all event types
-stackline.clickTracker = hs.eventtap.new({click}, --  {{{
-function(e)
+stackline.clickTracker = hs.eventtap.new({click}, function(e) --  {{{
     -- Listen for left mouse click events
     -- if indicator containing the clickAt position can be found, focus that indicator's window
     local clickAt = hs.geometry.point(e:location().x, e:location().y)
@@ -35,34 +50,27 @@ function(e)
 end) -- }}}
 
 stackline.refreshClickTracker = function() -- {{{
+    local turnedOn = stackline.config:get('features.clickToFocus')
+
     if stackline.clickTracker:isEnabled() then
-        stackline.clickTracker:stop()
+        stackline.clickTracker:stop()                     -- always stop if running
+    end
+    if turnedOn then -- only start if feature is enabled
+        log.d('features.clickToFocus is enabled!')
+        hs.alert.show('clickTracker has refreshed')
+        stackline.clickTracker:start()
+    else
+        log.d('features.clickToFocus is DISABLED ❌')
+        stackline.clickTracker:stop()                     -- double-stop if disabled
+        stackline.clickTracker = nil                      -- erase if disabled
     end
-    stackline.clickTracker:start()
-end -- }}}
-
-function stackline.start(userConfig) -- {{{
-    log.i('starting stackline')
-
-    -- init config with default conf + user overrides
-    stackline.config:init(
-        table.merge(
-            require 'stackline.conf', 
-            userConfig
-        )
-    )
-
-    stackline.manager = require('stackline.stackline.stackmanager'):init()
-    stackline.manager:update() -- always update window state on start
-    stackline.clickTracker:start()
 end -- }}}
 
--- 0.30s delay debounces querying via Hammerspoon & yabai
--- yabai is only queried if Hammerspoon query results are different than current state
-stackline.queryWindowState = hs.timer.delayed.new(
-    0.30, 
-    function() stackline.manager:update() end
-    -- cb(stackline.manager, 'update')  →  This should work but it doesn't
+stackline.queryWindowState = hs.timer.delayed.new(0.30, function()
+    -- 0.30s delay debounces querying via Hammerspoon & yabai
+    -- yabai is only queried if Hammerspoon query results are different than current state
+    stackline.manager:update()
+end
 )
 
 function stackline.redrawWinIndicator(hsWin, _app, _event) -- {{{
@@ -96,29 +104,24 @@ stackline.windowEvents = { -- {{{
     wf.windowMinimized,
 } -- }}}
 
+-- On each win evt above, query window state & check if refersh needed
 stackline.wf:subscribe(stackline.windowEvents, function() -- {{{
     -- callback args: window, app, event
     stackline.queryWindowState:start()
 end) -- }}}
 
-stackline.wf:subscribe(wf.windowFocused, stackline.redrawWinIndicator)
-
-local unfocused = { wf.windowNotVisible, wf.windowUnfocused }
-stackline.wf:subscribe(unfocused, stackline.redrawWinIndicator)
+-- On each win evt listed, simply *redraw* indicators
+-- No need for heavyweight query + refresh
+stackline.wf:subscribe({
+    wf.windowFocused,
+    wf.windowNotVisible,
+    wf.windowUnfocused,
+}, stackline.redrawWinIndicator)
 
+-- On space switch, query window state & refresh, plus refresh click tracker
 hs.spaces.watcher.new(function() -- {{{
-    -- Added 2020-08-12 to fill the gap of hs._asm.undocumented.spaces
     stackline.queryWindowState:start()
     stackline.refreshClickTracker()
 end):start() -- }}}
 
--- Delayed start (stackline module needs to be loaded globally before it can reference its own methods)
--- TODO: Add instructions to README.md to call stackline:start(userPrefs) from init.lua, and remove this.
-
--- hs.timer.doUntil(function() -- {{{
---     return stackline.manager
--- end, function()
---     stackline.start()
--- end, 0.1) -- }}}
-
 return stackline
diff --git a/stackline/window.lua b/stackline/window.lua
index f03f99a..410e879 100644
--- a/stackline/window.lua
+++ b/stackline/window.lua
@@ -115,7 +115,7 @@ function Window:drawIndicator(overrideOpts) -- {{{
         }, self.iconIdx)
     end
 
-    self.indicator:clickActivating(false)
+    self.indicator:clickActivating(false) -- clicking on a canvas elment should NOT bring Hammerspoon wins to front
     self.indicator:show(fadeDuration)
 end -- }}}