I am getting an empty sketch, when I am inserting custom structure as a weldment. See attachment
It sounds like your profile sketch does not have a library feature in it. Edit your profile sketch file. Right mouse on the Sketch in the feature tree and "Add to Library". Then say the changes.
I don't disagree with Wayne, but another option may be that your custom profile wasn't saved properly. I outlined the procedure I use in a post in this discussion, You might review it and see if it matches with the procedure you used.
I've been thinking about this, and I seem to remember getting that same error message a few years ago when I was just starting to use SW. I'm pretty sure the problem was that the sketch wasn't selected (highlighted) when I saved as a library feature part.
thanks for your help, problem solved
Retrieving data ...