If you compile a osx x64 or universal version the splash image and UnityPlayer.icns will not be included in the app bundle.
I have found no solutions to this other then to compile a x86 version and copy the “ScreenSelector.tif” and “UnityPlayer.icns” files to a temp folder then make a x64/universal version and copy the files in to that new app bundle.
It’s been there since 4.2. I solved it by making permanent versions of the files and copying into the bundle, though.
well I just recently went from 4.1.5 to 4.2.2 and hadn’t noticed it… 
Some freaking miracle happened and I could suddenly use 4.2.1 without it crashing all the time. And also 4.2.2 has been working nicely (KNOCK ON WOOD!!!) But I’m trying to submit a game to the Mac App Store and I have big problems getting it code signed. I am trying a post build script for now, but that takes the app without the icons and splash image and code sign it and make a pkg file out of it. And of course it is rejected by Apple for missing icons. And also for not having a correct architecture of the executable, even though I have tried x86, x86_64 and universal.
Anyone have any tip for these problems??
It’s possible they require you to use both the new and the old style of icons to be accepted these days. The new icon catalogs are a bit trickier than using a simple ICNS maker, since the only real tool is Xcode. But they’re basically just a directory and images, possibly with a plist index. I haven’t started digging into that much yet, but you should find some help and the occasional rant about it on the official dev forums.
Issue has been fixed in 4.3. Universal and x64 builds have proper icon and splash images