I don't know if you guys are having problems with ghost crew. It usually happens on the conning tower and shows up when you move to look somewhere else. A crew member appears and disappears in seconds.
I had the d3d_antilag101 in my main folder, I adjusted the RenderAheadLimit to many different settings to resolve the problem. The solution I found was just remove d3d_antilag101 files. After that no more ghost, I honestly don't see frame rates difference with it in or not, so its better without it in. No more ghost.
I would try to remove the d3d_antilag101 and see if it fixes the crew problem, it wouldn't hurt to try.