diff --git a/src/drawFieldOfVIew.m b/src/drawFieldOfVIew.m
index f3c314b..b41ddf4 100644
--- a/src/drawFieldOfVIew.m
+++ b/src/drawFieldOfVIew.m
@@ -1,6 +1,6 @@
 % (C) Copyright 2020 CPP_PTB developers
 
-function drawFieldOfVIew(cfg)
+function fov = drawFieldOfVIew(cfg, centerOnScreen)
     % drawFieldOfVIew(cfg)
     %
     % draws a red rectangle on the screen to materialize the field of view of
@@ -8,17 +8,25 @@ function drawFieldOfVIew(cfg)
     % stimuli if you know the FOV of the participant will be obstructed by
     % something
 
+    if nargin < 2
+        centerOnScreen = true;
+    end
+
+    fov = [];
+
     if isfield(cfg.screen, 'effectiveFieldOfView') && ...
-        numel(cfg.screen.effectiveFieldOfView) == 2
+        numel(cfg.screen.effectiveFieldOfView) == 4
 
         RED = [255 0 0];
         penWidth = 2;
 
         fov = cfg.screen.effectiveFieldOfView;
 
-        fov = CenterRect( ...
-                         [0, 0, fov(1), fov(2)], ...
-                         cfg.screen.winRect);
+        if centerOnScreen
+            fov = CenterRect( ...
+                             fov, ...
+                             cfg.screen.winRect);
+        end
 
         Screen('FrameRect', ...
                cfg.screen.win, ...
diff --git a/src/initPTB.m b/src/initPTB.m
index ba29173..986858f 100644
--- a/src/initPTB.m
+++ b/src/initPTB.m
@@ -22,6 +22,10 @@
     %
     %
 
+    % for octave: make sure information is not presented on prompt one screen at
+    % a time
+    more off;
+
     checkPtbVersion();
 
     cfg = getOsInfo(cfg);
diff --git a/src/screen/farewellScreen.m b/src/screen/farewellScreen.m
index abbe0ab..b826e93 100644
--- a/src/screen/farewellScreen.m
+++ b/src/screen/farewellScreen.m
@@ -5,6 +5,8 @@ function farewellScreen(cfg)
     Screen('FillRect', cfg.screen.win, cfg.color.background, cfg.screen.winRect);
     DrawFormattedText(cfg.screen.win, 'Thank you!', 'center', 'center', cfg.text.color);
     Screen('Flip', cfg.screen.win);
-    WaitSecs(cfg.mri.repetitionTime * 2);
+    if isfield(cfg, 'mri')
+        WaitSecs(cfg.mri.repetitionTime * 2);
+    end
 
 end