Add error checking to the file load handler and display an error notification on failure, instead of just always announcing success. This makes it easier to see the problems on Android and iOS. Android is getting permission denied on load from the file picker intent... previously iOS was having issues loading files too but is now working.

[Desktop Entry]
Name=Dynamic Windows Test
Exec=@prefix@/bin/dwtest 
Terminal=false
MultipleArgs=false
Type=Application
Categories=Application;Development;X-Red-Hat-Base;