Maybe be an issue with some additions that were made to Focus in post-Luclin being in effect here:
http://lucy.allakhazam.com/spellhist...32&source=Live
2002-10-16 11:15 Added Slot 6: Stacking:
Overwrite existing spell if slot 1 is effect 'STR' and < 67
2002-10-16 11:15 Added Slot 7: Stacking: Overwrite existing spell if slot 1 is effect 'DEX' and < 60
2002-10-16 11:15 Added Slot 8:
Stacking: Block new spell if slot 1 is effect 'STR' and < 1067
2002-10-16 11:15 Added Slot 9: Stacking: Block new spell if slot 1 is effect 'DEX' and < 1060
Cripple reduces STR by 68-75(?), which is less than +67 and less than +1067 so Focus (circa 2002) overwrites and blocks based on this historical update in Lucy.
IDK if this is present here, but may be of guidance to pinpointing the issue.