So far I've only had an issue with one program (or rather, a couple versions of the same program) in Snow Leopard. I do 3D renders in DAZ 3D's Carrara Pro 7. The first time I launched it, I had no text in the application. And I mean everywhere. No text on the menus, tabs... you name it. I also had Carrara 6 still on my system, so I launched it - same deal. Appears to be a font issue. So I went searching the DAZ 3D forums for topics about this issue and found a workaround.
- Go to your home folder Library/Preferences/DAZ\ 3D/Carrara\ 7/Preferences.txt
- Open the file Preferences.txt search for: FONT ""
- replace it with: FONT "Times"
Other fonts may work but I know Times does.