As far as the conflicts, I've gone through and fixed a few places that were extending through XFCP that still needed the vw prefixing. However, I still can't fix a bunch of stuff in the Parser and Formatter classes. These use generic property names that exist in vBulletin but don't exist in XenForo, and those could be a vector for conflict. Fixing that will require a major refactoring of the parser system across all forum platforms since the names are all shared and a lot of them are public to other classes.
I'm thinking I will have to implement a &vwData function on every parser-related class in all platforms, implement wherever direct property access is used, and use it to translate property names (model, instance, parser, for, item, et al are all unprefixed).