diff --git a/package.json b/package.json
index 482f6d7..1f9eb57 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "ifvms",
   "title": "ifvms.js",
-  "version": "1.1.4",
+  "version": "1.1.5",
   "description": "The Interactive Fiction Virtual Machines Suite - in Javascript",
   "author": "Dannii Willis <curiousdannii@gmail.com>",
   "license": "MIT",
diff --git a/src/zvm/io.js b/src/zvm/io.js
index 597a197..5be99f1 100644
--- a/src/zvm/io.js
+++ b/src/zvm/io.js
@@ -399,7 +399,7 @@ module.exports = {
 			if (this.version3)
 			{
 				this.statuswin = Glk.glk_window_open(this.mainwin, 0x12, 1, 4, 202)
-				if (this.statuswin)
+				if (this.statuswin && this.Glk.glk_gestalt(0x1100, 0))
 				{
 					Glk.garglk_set_reversevideo_stream(Glk.glk_window_get_stream(this.statuswin), 1)
 				}
@@ -409,7 +409,10 @@ module.exports = {
 		{
 			// Clean up after restarting
 			Glk.glk_stylehint_clear(0, 0, 8)
-			Glk.garglk_set_zcolors_stream(this.mainwin.str, this.io.fg, this.io.bg)
+			if (this.Glk.glk_gestalt(0x1100, 0))
+			{
+				Glk.garglk_set_zcolors_stream(this.mainwin.str, this.io.fg, this.io.bg)
+			}
 			Glk.glk_window_clear(this.mainwin)
 			if (this.upperwin)
 			{
@@ -1004,7 +1007,10 @@ module.exports = {
 					Glk.glk_stylehint_set(4, 0, 8, this.io.bg)
 				}
 				this.upperwin = Glk.glk_window_open( this.mainwin, 0x12, io.maxheight, 4, 203 );
-				Glk.garglk_set_zcolors_stream(this.upperwin.str, this.io.fg, this.io.bg)
+				if (this.Glk.glk_gestalt(0x1100, 0))
+				{
+					Glk.garglk_set_zcolors_stream(this.upperwin.str, this.io.fg, this.io.bg)
+				}
 				Glk.glk_stylehint_clear(4, 0, 8)
 			}
 			else