There would be all dupes of the maps since they are named with "v2" added, right? Anyway, I uninstalled Vol.4 first and then since no installer for v2 I copied the files as instructed in the readme. However, I've found that the speed boots/fire dome pickup is no longer in the list of mutators. Was this removed from v2? (The deflector/nightmare is still there.) Or does the new one contain all of them now even though the description text in-game doesn't say?
UPDATE: I found out the problem, v2 zip is missing the UTCBP3_Pickups.ini file!!! For shame.
UPDATE 7/10: So, this problem was rectified at some point and unannounced, I only found out when I had to reinstall everything new. heh