Hello Guys,
Regarding the update, we’ve submitted it to epic, so it’s hard to give an ETA on when they will release it for you, I’ll post here as soon as they reply that the pack is updated.
Regarding the positioning of the gun, on the gun base you have “VivePreviewController” mesh, if you turn the visibility on, you can see where the gun will be relative to the controller. You should not move this or the frame, but instead use the GunRoot for moving the placement of the gun. Let me know if this helps 
For the magazine, I would say that it should work for you to change one of the guns with a magazine, I have not tested this but from what I can see, you probably would only need to make sure physics is off on the spawned magazine, so that she stays attached to the hip. The guns are added on the “BP_ArcadePawnExample” with the “SpawnGunInHolster” function, you would have to create a similar one but for the magazine on one of the hands
Thank you