Plutonium

I used to play private matches like a year ago, but now I do not know how. Can anyone tell me what command I am supposed to type in the console to start a match? Also, I tried starting a game in a private match lobby, chose a map and settings but halfway through loading, I get this error:

What should I do to fix this? I keep finding an answer in the pinned posts but I am unsuccessful. Thanks in advance.

I saw the topic here that asks about bots, and I did the thing that is needed to spawn bots (the sv_cheats thing and bots). They spawned, but why are they just spinning around in place? Is it a). They are programmed to just do that? b.) I am doing it wrong/missing something in the FAQ/just impatient to see them move on their own? or c.) MW3 in plutonium is for online play and no bots?