I've done quite a bit of stuff with this concept with the TJI guys on my own server, so I'd like to get a few words in.

First of all: I highly recommend you use /devmap rather than /map. Having cheats enabled lets you use a number of commands in addition to actual cheats, including debug commands that can get you out of a tight spot.

Cinematics and cut-scenes don't happen in MP, it's as simple as that. Therefore, any maps which require cut-scenes to move you forward in the level (t2_dpred being a notable example) have to be replaced by something else... which is the main reason I recommended having cheats enabled. Don't use noclip unless you have to, but it's nice to have there.

NPC Spawners function differently in MP. The TJI guys like to use t2_trip as a cheats-enabled FFA area. Unfortunately, we learned the hard way that there are one or more "rogue spawners" in this map which continue spawning as long as the server is running, and will eventually crash it unless you /npc kill all once every two or three minutes.

And, of course, the win and lose game conditions aren't present in MP (although, interestingly enough, the code for them are). This means that even if you do make it to the end of the level successfully, you won't know it unless you're familiar with the map in question.

Because of all this, there are several maps which are all but unplayable in MP, and a bunch that require workarounds such as noclipping. That being said, there are also some that work quite nicely with no fooling around at all. Here's a partial list of some of the ones I've tried:

t1_surprise: Playable. The control panels in the sandcrawler don't work. Noclip is required to get to the lower levels. The R5 unit is there but its script doesn't work, so the level essentially ends when you get to it.

hoth2 and hoth3: Working. The Hoth maps can safely be played without cheats enabled, as long as you don't mind manually moving to the next map. As a bonus, the bosses at the end even spawn correctly.

t2_dpred: Not Worth It. Since the introductory cut-scene doesn't happen, you begin the level locked in your cell. Noclip is required to get out. Again, many control panels don't work, and the "security key" item doesn't exist in MP, so a lot of noclipping and extensive knowledge of the level are required.

t2_trip: Not Worth It. NPCs don't spawn (except for a couple of rogue spawners near the middle), and none of the cinematics happen. It's a fun map for swoops and ships, but that's about it.

t3_rift: Working. Since not much happens in this level anyway, there's nothing to worry about. The scripts at the end don't really work properly, but that's not a major part of the level.

And the rest of the maps all follow those same general rules. If there's any maps you have specific questions about, or you'd like me to post descriptions of more of them, feel free to ask. Hope that helps!