yup Savage is right.
Edit the mission through Multiplayer, and your respawn will work. I had the same trouble only a few days ago and this was the problem.

Sorry to bump this old thread, spent hours on this problem this evening and still can't get it to work..

I've found that if i export the mission to the multiplayer missions folder, i can access it as a LAN game, and Multispawn then works... but this is kludgy workaround for a single player mission.

The ALiVE docs say that the Multispawn module is supposed to replace the savegame function, which causes a crash when using ALiVE... but it seems singularly incapable of fulfilling this requirement.

Am i really likely to suffer crashes if i just enable savegames? I have 12gb ram.. Having to host a LAN game just to get Multispawn working seems horribly awkward..

Never had to use respawn before, but honestly expected that i could just place the module and it would automate the process (which seemed the whole point of a dedicated module in the first place).

Additionally the ALiVE wiki says nothing about having to save the mission to the multiplayer folder... yet the provided instructions just will not work in singleplayer - no matter what respawn markers i try, i briefly see the "respawning" message when dying, but then it just goes to the restart / exit options..