Hello Sslaxx,
I also had the same issue, but was able to overcome it by changing the workdir value. I know you wrote that you already tried it but are you sure that it is just like this;
std::string workdir = "C:/ProgramData/ENIGMA/";Notice the / at the end of ENIGMA, in the first few posts on the other thread it doesn't have that. If you changed it but didn't have the slash in the end, it is the reason why it didn't fix this problem.
Another thing, that I also had to do in order to fix the problem, was that I needed to manually create the ProgramData/ENIGMA/ folder in C: driver.
Hopefully you'll get it working!

EDIT: Worth mentioning; obviously if you use other driver letter than C:, then you just change the driver letter to your one
