hmm--what kind of processor is it? any chance you can just dilution ventilation for the room? we have a big old slot hood behind our sink, and the roller transport processor just uses the dilution effect of this hood. when you stand at the sink & work though? it's like a curtain of air flowing across the trays and off the back. you never really smell a thing--great for toning. what it was designed for. our film darkroom is just dilution ventilation with the exhaust part being right above the deeptank line. the wing lynch machine is pretty much okay out in the room.
there's a small book that has to diagrams of local exhaust hoods and slot hoods and the like. we got a copy somewhere, I'll see if I can find the ISBN number if you're interested, I'm sure a library would have it.
I was looking at your diagram though, and was curious if you had room for the nitrogen tank for the WL? you probably need about a foot and half square for that, and someway to chain it to the wall. One thing you could do, depending on the WL model, would be to get the solution bypass valves (if you don't have em already)--this way you can run the fix, bleach etc into holding tanks for reuse or into a recovery unit in-line with a drain. something to think about....