I've been searching for a solution for this for several months to no avail. Upon clicking 'Drive' I get a locked screen as the 'Preparing' window opens, CM crashes and I must 'x' out. When restarting CM and clicking 'Drive' AC starts and runs without issue, every time, without fail. Its not a big prob, I just expect it and go with it. I've searched for months, log files (not sure what to look for), numerous 'CM crashes on start up' searches/ forum posts and trying different suggestions, shaders, shader patches etc.. I'm running win10, AC thru steam, latest CM and Sol on a 5 yr old rig. I'll post any screen shots needed. Its a great game esp. with CM (but I'm sure you know that). Thank you in advance- 3G
