Ok, I've got it working on one laptop (newer one). What I had been doing was dropping it into a "Program Files\Mythruna" folder. When I leave the folder on the desktop, it works just fine, but trying to run it from Program Files, it doesn't work for Single Player mode.
I haven't tested this from 15 dif directions yet.. just got it working so the kids could enjoy building.
On a side note, I'm impressed with how easily the server gets up and running... it worked without any issues or adjustments. Nicely done!
Nice that the server worked well for you.
On the program files issue, that is weird. Perhaps it's a permission issue or something. If it got to the Mythruna menu for selecting a game then it was at least able to extract the DLLs but then maybe couldn't create the mythruna.db folder. If it didn't even get that far then it couldn't even create those files.
Glad you were able to find a way to get it working and now there is one more thing I can check when other people have problems.