Index: pronterface.desktop
--- pronterface.desktop.orig
+++ pronterface.desktop
@@ -4,8 +4,8 @@ Name=Pronterface
 GenericName=Printer Interface
 Comment=Controls your 3D printer
 Icon=pronterface
-Exec=/usr/bin/pronterface.py %f
-Path=/usr/share/pronterface/
+Exec=${PREFIX}/bin/pronterface %f
+Path=${PREFIX}/share/pronterface/
 StartupNotify=true
 Terminal=false
 Categories=GNOME;GTK;Utility;Graphics;3DGraphics;