I'm having the same problem. My p99 with Wineskin used to launch fine, then I took a 6 month break or so, came back to the game (now with Mojave) and the game takes like 3-5mins just to launch.
If anybody knows how to fix this please help.
This is the installation method I used.
https://www.youtube.com/watch?v=_xfNbEUVweM