ZDoom

Ok, thanks for quick response. However I have some more questions from your answers. As long as you use a version post-GPL-ification, preferably after the resource split too. (So 3.5.0 should be just fine) What if under 3.5.0? I found the information that license was changed when 3.0 released under ...

I saw a mod something looks like standalone is going to be commercial. AFAIK, ZDoom and GZDoom licensed under GPL v3. So shouldn't be all source codes must be distributed as GPL v3 as well? And the term "source code" in here, what exactly, meaning of? Is this meaning of includes all action scripts ...