I am indeed using the compiler included in the svn.
I never used to have this problem, it's only now that I'm trying to get the latest version after not having net for 4 months that this has started. Nothing on my computer has changed since compiling last either, which just leaves me without a clue.
Dragging files on to spcomp.exe yields no .smx in the compiled folder.
EDIT: Have triple checked any possible interference from my firewall, both spcomp.exe and compile.exe are trusted applications and have full access to anything they need.
http://postimage.org/image/jbs0xs3cr/I apologise for not cropping, lack of time. There's really not much point in that screencap, but honestly that's all there is to go by as far as I can see. The .smx appears in the compiled folder, but when I tried to compile every file individually and upload it just started without war3 and went straight to nilla.
EDIT #2: Ok, so basically I've tried to use the compile.exe and spcomp.exe from other locations and none of them have worked, and also it appears that I can not compile any .sp anywhere inside my srcds folder. I had a friend upload his War3SourceP folder for me, and although compiling works fine for him, it still gives me an internal error.
Am srsly out of ideas.