I can reproduce this problem on both my DAW Mac pro and my slave Macbook Pro.
Doubleclicking a .vesp64 file loads the template, but crashes VEP6 when finished loading. Opening VEP6 and then loading a file via "Open Server Project" works.
This is highly annoying since I'm using keyboard macros to open template files.
Edit: Mac Pro DAW running OSX Maverick, Macbook running Yoshimite.