Moving from FREE to PRO
 

Please treat this as a yes/no question. If I uninstall bs.player free and install bs.player pro will the pro version access all of the same codecs and LAVs that the free version did?
Reason: i spent several hours yesterday getting the free version of 2.76 to decode h.265 compressed files. Finally, it does and i don't want to lose it.

NO.
You can completely uninstall BSPlayer free and after install BSPlayer pro. When installing, allow only LAV filters and AC3Filter to be installed.
This is all you need to play most of the files. LAV filters will decode H265 with no problem.
If you had any problems before, probably you have other codecs / codec packs installed on your system that interfere with the ones above.