go to an adobe preset workspace, like color, then go back to your custom preset and everything should be ok. (worked for me)
As for the rest, it seems like the timeline points to problems with your system and 14.5 from 14.4, if you can roll back to version 14.4, from inside the adobe creative cloud program, adobe kinda rushed this one to get it ready for adobe MAX conference.
As for DV... I hear its a steep learning curve from P Pro
I've edited a few projects in resolve and didn't like it. It's great for color correction but media management, connecting to media, proxy workflow and alot of other stuff all seemed unnecessarily unintuitive... but the price is right... I work with a cameraman who shoots stock footage and works in resolve and he's always calling me cause he can't figure something out...