It shouldn’t matter but I haven’t tested this myself on a VM. Either way give it a shot from an actual windows installation if possible.

Otherwise if you’re running it through Wine, run L2.exe in your shell (using wine /path/to/L2.exe or whatever other arguments you pass it) and read the debug trace on the console after trying to set a crest and getting a critical error. Maybe it’ll help you figure out exactly where the problem lies.