Customized tool using external axis

Hiya, new member, M.Sc student having a great interest for simulation equipments.

So, I am trying to figure out a way to create a tool (spotwelding gun) and to use an external axis for the control system to make the joints move. As I try to create a system with my created tool I just get the message seen in the picture below.



My guess is that I messed something up when creating the tool itself. But after a little searching on the forums here I'm thinking of 2 other main reasons:

1. I need to get the Add-in "External Axes Wizard".
2. It doesn't work like this at all, and I need to approach the problem differently.

Any ideas?