I had similar problem on windows with my laptop when running Moi with intel graphics processor (optimus technology), so could be also a drivers config or version.
I seem to remember having a similar problem after updating my graphics card driver. The update included some feature that stuffed things up. Had to go back to the earlier version, I think.
For this particular problem on the Mac it is a bug in Wineskin which is only encountered when running on the recently released High Sierra operating system. The OS reports GPU information in a slightly different way which then exposes a string parsing bug in Wineskin.
