I'm trying to run LFS Dcon on my Debian headless server via PHP (to start/stop it). Installed Wine and when I run DCon.exe it runs fine, but when I run it via PHP it starts (it seems, it gets a PID), but seems to close right after that.

It used to work fine with 100% the same code, so I don't know what's different now on this new server. I'm using Mono to run my InSim and that just works out of the box after installing Mono. Would it maybe be possible to run DCon with Mono? When I try to run it I get "Cannot open assembly 'DCon.exe': File does not contain a valid CIL image.".

If anyone can help me with either Wine via PHP or Mono, please let me know!

You can't run Win32 binaries with Mono.

Mono can only run CIL binaries (and not all of them).

If it fails via PHP, it might be because it's expecting an X server (it's been a while since I ran LFS in wine), so you might need to pass some ENV variables to it.