Unity crashing when building, creating new scene, changing scenes and exiting.

Hi

We are having a really bad time with Unity right now. Since we updated our project to 4.3, we have been experimenting frequent crashes when building, creating new scenes, changing scenes or exiting Unity. These crashes do not happen always, but it's getting pretty annoying to apply the workaround we have discovered (and which don't always work) every time.

The workarounds are: rebuilding the Library folder, loading another project and then reloading the project and modifying random things inside scenes before building.

Our project is very large (16 GBs) and we use several plugins (2D Toolkit, 2DColliderGen, Spine, Xffect, InControl, etc)

It would be really nice if someone could help us with this issue since it's really really slowing us down. Any kind of suggestion would be great: project settings, workarounds, etc.

Thank you for any help