If crystalized buildables are flickering for you, change your Anti-Aliasing to something that isn't TAA. This should also fix flickering text on signs.

If you are experiencing rubberbanding/lag with custom assets, try to place the map in the same place as other vanilla maps (Russia, PEI, etc). If you are still experiencing problems, add "misc.dont_enable_this true" to Execute.config. This will disable unturned's anticheat (VAC and Battleye will still be active) and should remove the rubberbanding issue completely. I don't reccomend doing this on a public server but if you are playing with friends, I highly encourage it.