Styles under you CUSTOM button are special non-standard styles...extras if you like which can be replaced by other CUSTOM styles - there are a few around on the internet.
There is no logical reason to move any standard styles into the CUSTOM styles area but if you really want to then...
1. Program menus
2. Composer
3. Pattern copy in the right direction
4. Custom style copy from memory to custom
Beware of getting the direction correct for each maneovre (not sure how to spell that word)
4.
_________________________
Roger M