Yeah that's how it works in zandro/skullie it adds the no monsters flag, but then what is the -nomonsters parameter for?
I'll change it, i already changed other flag related things. But this is a minor thing, actually deathmatch doesn't work. Seems nobody has tried it. Yeah it was broken since Skulltag (probably when they added the new modes), it was fixed in zandro3. I'm talking about the deathmatch cvar being ignored the command line parameter works (but launchers use the cvar). There was a hack to make it work with old compilers and it depended on the link order of the files and when they moved to VS 2015 it rose its ugly head. I mean sure there are some hacks in LZDoom but this one seems from another dimension. Remember that this is a VS 2017 build.
And as i said coop was broken too still in 0.97 after many years (monsters didn't gib and only worked in Doom). Then they updated to an unstable ZDoom codebase (WIP 2.2).
I already mentioned in the discord the disconnect command using I_Error thing fixed later. Well turns out zan 1 and 2 were riddled with bugs (so my fork is too). Besides there were problems with unlagged (may be here too i'm not sure). Well, too bad. Also menus were horribly stretched on widescreen displays until zan3.