Howcome some games and utilities that were written for 2002 such as Nuclear Time, EQ, anything from Aim Productions, CPUID, Space Reclaimer, etc. work fine with 2003 and some software like StorageTools didn't until the fix was released and SorceryPDA still doesn't?

Stepping Through Life...

Some of the API's (simply put, requests to the OS) have changed between versions of CE. So, if the developer used one that changed, they'd have to rewrite some of the code that used it.