Thanks for your bug report. The custom dialog code does not handle spaces at all in this case. The only reason that format is working for you is that some of the Windows image APIs parse spaces. I have extended the icon code to remove extra spaces before calling the APIs. As far as I can tell, this shouldn't break backward compatibility but will need testing.
As for the disabled/hidden icon on startup, this also applies to hotlinks. These have always worked this way and there are no plans to change this behaviour.
