If I can save someone the four hours of bashing my head against the table I just went through with one simple tip, maybe it won't have been in vain.
I went through the tutorial fine and was ready to start a clean, non-template-based "hello world" game, and just wanted to get a custom splash screen up. I made the screen with GraphicConverter, saved it as a PICT file, and followed the tutorial and a recipe from another thread about "minimum game requirements" to create a basic, beginning skeleton. It came up with a black screen every time. Long story short: I was tearing my hair out, spent four hours triple- and quadruple-checking every step, comparing the events and locations and game info and so forth with working sample games, and I was SURE it was all correct. It was at the point where I was beginning to suspect filesystem damage, and then out of sheer desperation I changed the bit depth of the PICT from 8 to 16, and pow, it worked.
I couldn't find anything in the manual about this, and the previews of the splash screen and the splash screen itself were rendering fine from within the editor, but when running the game in window mode, it wasn't displaying. So, there it is: make sure your PICTs are 16-bit, not 8-bit. Anyone who wishes to refine this tip with more detail is welcome. I'm going to bed.
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