Why does TestStand take so much longer to load a Vi from a LabVIEW prject than calling directly?

I have done some tests where the same VI loaded from a LabVIEW project takes much much longer to load in TestStand vs calling the VI directly. The project file I'm using is large, and am guessing it tries to load all the files in the project into memory?? Any ideas on how to fix this? I would like to continue calling VI's using projects in TS but the load time can be ridiculous. Thanks