diff --git a/v2/internal/ffenestri/ffenestri.go b/v2/internal/ffenestri/ffenestri.go
index a448e7ce0..2d5b7330f 100644
--- a/v2/internal/ffenestri/ffenestri.go
+++ b/v2/internal/ffenestri/ffenestri.go
@@ -167,7 +167,7 @@ func (a *Application) Run(incomingDispatcher Dispatcher, bindings string) error
 	}
 
 	if a.config.Colour != 0 {
-		r, b, g, alpha := intToColour(a.config.Colour)
+		r, g, b, alpha := intToColour(a.config.Colour)
 		C.SetColour(a.app, r, g, b, alpha)
 	}
 
diff --git a/v2/internal/ffenestri/ffenestri_client.go b/v2/internal/ffenestri/ffenestri_client.go
index 7af51d87f..de1ad5c94 100644
--- a/v2/internal/ffenestri/ffenestri_client.go
+++ b/v2/internal/ffenestri/ffenestri_client.go
@@ -115,7 +115,7 @@ func (c *Client) WindowSize(width int, height int) {
 
 // WindowSetColour sets the window colour
 func (c *Client) WindowSetColour(colour int) {
-	r, b, g, a := intToColour(colour)
+	r, g, b, a := intToColour(colour)
 	C.SetColour(c.app.app, r, g, b, a)
 }
 
diff --git a/v2/internal/ffenestri/ffenestri_darwin.c b/v2/internal/ffenestri/ffenestri_darwin.c
index 526c7e611..9fca02cbf 100644
--- a/v2/internal/ffenestri/ffenestri_darwin.c
+++ b/v2/internal/ffenestri/ffenestri_darwin.c
@@ -158,11 +158,27 @@ void UseToolbar(struct Application *app) {
     app->useToolBar = 1;
 }
 
+void applyWindowColour(struct Application *app) {
+    // Apply the colour only if the window has been created
+    if( app->mainWindow != NULL ) {
+        ON_MAIN_THREAD(
+            id colour = msg(c("NSColor"), s("colorWithCalibratedRed:green:blue:alpha:"),
+                                (float)app->red / 255.0, 
+                                (float)app->green / 255.0, 
+                                (float)app->blue / 255.0,
+                                (float)app->alpha / 255.0);
+            msg(app->mainWindow, s("setBackgroundColor:"), colour);
+        )
+    } 
+} 
+
 void SetColour(struct Application *app, int red, int green, int blue, int alpha) {
     app->red = red;
     app->green = green;
     app->blue = blue;
     app->alpha = alpha;
+
+    applyWindowColour(app);
 }
 
 void FullSizeContent(struct Application *app) {
@@ -225,6 +241,8 @@ void* NewApplication(const char *title, int width, int height, int resizable, in
     result->maximised = 0;
     result->minimised = 0;
 
+    result->mainWindow = NULL;
+
     // Features
     result->frame = 1;
     result->hideTitle = 0;
@@ -234,7 +252,6 @@ void* NewApplication(const char *title, int width, int height, int resizable, in
     result->hideToolbarSeparator = 0;
 
     result->titlebarAppearsTransparent = 0;
-    printf("[l] setTitlebarAppearsTransparent %d\n", result->titlebarAppearsTransparent);
 
     result->sendMessageToBackend = (ffenestriCallback) messageFromWindowCallback;
 
@@ -727,12 +744,7 @@ void Run(void *applicationPointer, int argc, char **argv) {
     msg(mainWindow, s("setStyleMask:"), decorations);
 
     // Set Colour
-    id colour = msg(c("NSColor"), s("colorWithCalibratedRed:green:blue:alpha:"),
-                          (float)app->red / 255.0, 
-                          (float)app->green / 255.0, 
-                          (float)app->blue / 255.0,
-                          (float)app->alpha / 255.0);
-    msg(mainWindow, s("setBackgroundColor:"), colour);
+    applyWindowColour(app);
     
 
     // Setup webview
diff --git a/v2/internal/runtime/goruntime/window.go b/v2/internal/runtime/goruntime/window.go
index e7e4c06c5..7c478da7f 100644
--- a/v2/internal/runtime/goruntime/window.go
+++ b/v2/internal/runtime/goruntime/window.go
@@ -16,7 +16,7 @@ type Window interface {
 	SetTitle(title string)
 	Fullscreen()
 	UnFullscreen()
-	SetColour(colour string)
+	SetColour(colour int)
 }
 
 // Window exposes the Windows interface
@@ -54,8 +54,8 @@ func (w *window) UnFullscreen() {
 	w.bus.Publish("window:unfullscreen", "")
 }
 
-// SetColour sets the window colour to the given string
-func (w *window) SetColour(colour string) {
+// SetColour sets the window colour to the given int
+func (w *window) SetColour(colour int) {
 	w.bus.Publish("window:setcolour", colour)
 }
 
diff --git a/v2/test/runtime/runtime.go b/v2/test/runtime/runtime.go
index 4399b821d..fefb576c7 100644
--- a/v2/test/runtime/runtime.go
+++ b/v2/test/runtime/runtime.go
@@ -62,7 +62,7 @@ func (r *RuntimeTest) UnFullscreen() {
 }
 
 // SetColour will call the Runtime.UnFullscreen method
-func (r *RuntimeTest) SetColour(colour string) {
+func (r *RuntimeTest) SetColour(colour int) {
 	r.runtime.Window.SetColour(colour)
 }