@dga223
that depends largely on the version of your previous build ... assuming that that was a beta version
(= before it was added to trunk) i would personally:
- move all existing files on card to a backup folder on your computer
- write the new version to card
you can then experiment if your previous .cfg is usable (probably not, lots of changes recently)
re-formatting should not be necessary (but doesn't hurt either)
wim
BTW you might also be interested to know that zeno made a config editor, check it out here:
An Editor for CHDK.CFG Files