The beta has some very large problems, actually 3 of them.
1st Problem: When running, and when running I mean the character you play as, the screen jitters around. Could this be an attempt at realistic running? I dont know if its intended, but its very annoying. Tried many things in options to fix it, but nothing has changed.
2nd Problem: The game tends to increase game speed by a lot at random times. This is a critical problem, and should be fixed if possible. The spike in game speed is always random, and its very frequent.
3rd Problem: Dont use Vavoom. Its a very unpredictable engine, meaning it can mess up wads and randomly crashes games at times. I would suggest using Skulltag/Doomseeker and make the entire game a .wad instead of all pk3(s). Using this method should increase game performance and capabilities.