Was able to make a new RM8 file and put two people in it, save, quit and restart and then import a GEDCOM of 370 people downloaded from WikiTree, and merged a couple of duplicates.
Running RM8 Beta on 64 bit Linux MX-19 distribution on a Lenovo Thinkpad X270. Sometimes Rootsmagic is a bit sluggish, and if I try to sync with my Ancestry account it freezes (but this may be specific to me, others report success with Ancestry and mine freezes in both RM7 stable and beta RM8 - happens when I click Sign-On to Ancestry, so it think it is settings related to my account - if I run RM7 stable on Windows 10 I have no problem - but RM8 beta also freezes running on Windows 10).
Dont know where the problems lie yet - have to learn to tweak bottles and saved configuration settings (maybe Registry problems).