Unfortunately, there seems to be a dealbreaking bug with sockets. When Bake Meshes is disabled, you get proper pivot points but all the sockets exported in GLFT are zeroed out to origin:
When Bake Meshes is enabled, the pivots are zeroed out to origin but the sockets are on the right places:
This is quite embarrassing as for proper assembly of hard surface hierarchies, you need both: You need correct pivot locations and you need correct socket locations. With Bake Meshes ON you get wrong pivot locations but correct socket locations, with Bake Meshes OFF, you get correct pivot locations but wrong socket locations