Saving not possible. Too many open files (!?)

I’m working on a rather big project. The timeline stretches over 3 hours with material most of the time and 180 tracks. The project takes between 16-18 GB ram (pic2). I though have 64 GB on my computer, so there’s plenty left.

It seems like it’s a limit within Cubase, cause I can have the project working, but if I copy/duplicate a section of 3 minutes, it suddenly won’t save. This both counts for “Save as new…” as new version and a regular save. When doing so I get this message (pic1):

“The project could not be saved, because:
An unexpected error occurred. The system’s description is: Too many open files
No new project could be created.”

I’ve tried a few things, and cleaning the Pool seemed to give me a tiny stretch and made it sort of possible for me to save the session I was working with when I first time got the message.
Now I’ve tried to delete longer parts of the project (simply deleting in the whole timeline) and it seemed to make it possible to duplicate a section and save… But quite frustrating that I can’t have the whole project in one, when it comes to mixing and versioning of the pieces ect!
I’m not sure but the average load also seemed to have gone up quite a lot suddenly!

I’m on 10.8.4, 64GB ram, i7 3930k.

Skærmbillede 2015-09-19 kl. 15.19.15.png
Skærmbillede 2015-09-19 kl. 14.44.58.png

And to add, now the session I worked on has been totally messed up with some of the files.
I get the “Image under construction” message in the pool, and no matter what I do, it doesn’t restore/recreate it. Also for some reason it thinks that some of the files have gotten another location then the Audio folder (see pic).

I think I’ve tried all possible solutions, changing the folder names, removing image files, opening old versions, resaving, restarting ect. at least I’ve spend 4 hours trying to solve the problem.
I find non, and imagine it’s in connection with the “memory” error!
Skærmbillede 2015-09-19 kl. 17.52.03.png