Upgrading to Capture One 20 - updating Styles

Hi there,

I've recently upgraded to Capture One 20 from Capture One 11 and wondered do I need to delete the old styles and re-import them again or if i re-import them again will they just override the old ones.  The program has been really glitchy, crashing and exporting images with digital corruption since the upgrade and I wonder if this is the issue. I'm running Mac Catalina 10.15.5

Any advice is greatly appreciated! thanks, Mark