Bug with fonts in my game (well, not exactly bug)

When I opened one of my games in 1.0.1 and tried to test it the all fonts weren't visible (it didn't even fall back to default one). This happened to all my projects (Fear of Eights, Tetris Invaders and my secret project I working on).


At first I thought it was bug, so tried to make testcase in new blank game. However the fonts (both default one and custom one) were here. Now I'm confused - why fonts are visible in brand new game and aren't in older one? Here is zipped Fear Of Eights so you can check what is wrong.

The same thing happened with me, and was fixed by opening the font in StencylWorks then re-choosing which font it uses. Try that.

Thanks, helped. But why it happened in first place, anyway?