If you changed the game modes to the maps your server is running to Co-Op then you should already be having bots in the server by now. Also note the amount of bots you will have is determined by the max players your server is set to.
Also note I deleted the duplicate thread you made in the General Discussion section. You only need to create one thread for a single question.
No it should not make a difference. The only way I can see the bots not showing up is when the server is in fact not running the map in COOP mode....
Have you tried uploading a custom maplist.con to your server? Also the bots don't "Join". They are not part of the player count so your server will report as empty even with bots in there. Only humans count towards the player count that you see in the server list. Have you actually connected to the server with your game? The bots will be there. They just don't show up in the player count.
Those questions I'll have to leave to the next person to answer unfortunately. I don't think there is away of limiting the amount of bots on your server without also limiting the amount players. Perhaps there is a way and I'm not remembering it right now. Sorry.
I put that line in AI.con (in the map's root folder), with the value changed to 20, right below some other lines with "aiSettings.xxx" and started that map with 32 slots in COOP. Server and client running stable (did it SSM), 20 bots on the map, 32 slots given out by the server.
Ive tried to put aiSettings.setMaxNBots 24 in my dedicated server maplist and serversettings.con also created AI.con file and popped the setting in but after reboot still getting 64 bots?
