Corona SDK Pro Tip of the Day #23
Filename casing

Keep all your filenames in lowercase. This way you will never get case sensitivity errors. Especially if you are developing on a Windows machine or on a Mac with a case-insesitive filesystem.

Android and iOS are both case-sensitive.

lib/good_filename.lua  
lIb/AVeryBAdFilename.Lua  

The only exception are font files, which have to be named exactly as the font name.

Indie Game Developer