Address of the crash? Still the same?
re-downloading maps, reinstalling... hmm it doesn't convince me much.
Do you think a pure server would let you play with a pk3 with the wrong crc, without telling you anything? If a map is not in the pure list, it's just a map that is not played in that server. I'm not going to delete all my gammajump maps just because they aren't in the pure list, for example.
I know you have to try something, but imho it's either a driver issue or a problem with memory allocation in the game (even though I wonder why the game doesn't complain, then. Do you have enough com_hunkmegs?) Maybe the pk3 filesystem (too many pk3s? tried pk3 cleaner?) fails to load a file, it could be your config as well, but you would crash much more often in that case.
Your game crashes when it's drawing the 3d scene (I checked what's at that address in ET), so the first thing people would think is a driver problem (but then - why not on jaymod, since the engine is the same??)
You play in a pure server so it's guaranteed that you have the same pk3s everyone else has. (Well, cheaters can use unpure pk3s but you are not a cheater, so it doesn't count here). Unless there is some bug in this thing, redownloading a pk3 won't fix anything. Try to open a pk3 with a hexadecimal editor and change a single byte. You will be forced by the server to redownload it, just for a single wrong byte. If not, it means the pk3 is ok.
Or maybe you have too many pk3s, because there is a maximum limit afaik.
Try if you can see the address of the crash, if it's still the same as before.