That's exactly the same problem I am having. I have purchased some third party VIs that do not have diagrams. Previously in LV6.1, I could build them into an executable, but now with LV7.0 I can't (even though I now have the LV7.0 versions of these VIs). It seems that NI have changed the rules without telling anyone.
A work-around that I have tried successfully is to get DLL versions of the VIs.