IF it was the Mutara Fed starship one, yes it was withdrawn, leaving the USS Warwick map the only Fed starship interior with a engineering section usable in the foundry ATM. I can only assume that the map had been included in the early build 'by accident' because it is for an unpublished mission as of yet. I do wish someone would come out and say 'This map was withdrawn', or if I am oversupposing 'opps this map should be there, lets patch it' Regardless I haven't been able to clear all the resource errors off it to try and republish the map, and it was one that I really wanted to play with triggers on too.
I am running into this same problem you had with the error about the resource not found.
I was using the Mutara Nebula map template and still it will not work to allow me to publish my mission. I would hope that a fix can be found without having to go through a lot more work to come up with a new map to fix my mission.
Hopefully the devs will be able to give me more answer and I apologize for jumping into your thread but since I was having a similar issue I thought it would be okay to post here.
No need to apologize. Knowing that other people are having this problem helps conclude that it's the actual Mutara Nebula template itself and not just the backdrop.