! It's because PM checks mods against current file. Upgrade works by removing old changes from current file and applying new changes - which can't be applied as long as the old changes are still there - that's why PM shows that error.
+ more configuration variables in sboxDB.php
+ made background and text color of sbox theme-dependent. Alternating colors can be specified in settings for bright and dark themes - should work for all themes where there's a properly set windowbg2-class
* rewrote uninstall-code to SMF-package-sdk-example
