I have this issue where everytime I enter a house, near the entrance, my screen turns black.

I've had that particle issue working on my blood mod. Still can't release the V2 Update due to this issue plaguing it.

My 750 ti not supported this map

It should be fixed now.

They are but for some reason they decided not to work. Only Gmod likes to do this.

I think there's a few particles that were not included

Attempting to create unknown particle system 'waterfall_tower_medcenter_spray' (x8)
Attempting to create unknown particle system 'snowfall_ground' (x10)

Oh yes.

YEAHHH

Yes

AI nodes and Nav Mesh?

Yep I use Slammin'. While setting it up for the first time, I ran into some issues with the compile options and the -both option didn't work then, so that made me think that LDR was no longer supported. This was obviously not the case after all and I just compiled it earlier today. I should be able to release an update with LDR tomorrow.

did you use slammin to compile? if so add -both to the parameters to compile LDR and HDR

This map uses a 3rd party compiler for improvements in lighting, and from what I gathered it removed the support for LDR mode. I'll see if I can include an LDR version also. Unfortunately for now you'll have to use HDR mode.

Could you compile an LDR version too?