SetupTraceNodes running out of RAM

[Ed]

I've been working on a new DM map this week and everything was compiling fine. Lighting took about 90 seconds. The last working build I did was last night. I then made a couple of caulking changes and now it doesn't compile.

It gets to SetupTraceNodes which previously took several seconds and now it just gobbles up RAM and gets nowhere. It ate 2Gb, so I put another Gb in and it took that, then I went to 4Gb and it ate that. Still taking 10 minutes to do something that previously only took a few seconds and then ending at a safe_malloc error meaning it's out of RAM. There's no way I'm going out and buying 4x2Gb on this as before it used perhaps 100Mb and only took a few seconds on this task. Something in the map is broken. It has no leaks and has given no previous errors.

I have tried lots of lighting options including -lomem which seg faults. I have also tried both the stock q3map2 and div's build.

Here it is as a pk3 with an unlit BSP and the .map file, I'd be interested to know if anyone can get this compiled as is or if there's anything that needs fixing:
Edit: Link pulled.

The structure of the map is mostly complete, hinting is still to be done, item placement is very sparse for the moment. Some textures are missing from this pk3. Any comments about the level in general also welcome.

[Ed]

I've reverted to a previous version of it. No major loss particularly as I've now been getting rid of some stuff I don't like anyway.