you COULD add singleplayer maps to multiplayer. I believe a mod like this already exists for the pre existing MOHAA game. With that said, OpenMOHAA will support all file types that MOHAA does so it should be easily transferable so to answer your question yes it should be doable.
And as far as making the quality better, I believe that is also part of our to do list.
Ehh. Please, do read the FAQ before asking questions. It has been said a couple of times already: OpenMoHAA is not a mod! We are not making maps or anything, we only work on the code of the executable files that run all the stuff from the PK3s.
The only problem with that will be that we would have to repackage all the pk3 files. It's not difficult but then it may not be as backwards compatible with MOHAA as we would like not sure. I'll wait to hear Rookie One's reply to see if this is do-able or not. I'm sure it's do-able just a matter of whether or not it's ethical I suppose.
is it possible to save the leans from mohaa, but preventing selfing for example? If so, it would be really perfect. Something people were waiiting for a long time
It's not about loading times, it's just impractical. Introduction of a new compression format would make repackaging the 1,5GB of stock MoHAA media necessary. And why would anyone do that just to save a couple of megabytes of disk space? Can't be arsed.
It's understood that we'll try to avoid all the bugs. Please read the first post in this topic before making requests.