How to move a bunch of components in an assembly - transform tool not working?

I imported an assembly and now the components are "fixed" but I want to move a sub-group of them to another location.  Doing "edit definition" I can move a single component using the dragger.  But I have several (hundred) to move so doing so one by one isn't appealing.  I guess I can restructure the ones I need to move into a sub-assembly, then move the subassembly with the dragger, and then restructure out into the parent again, but seems tedious.

I found this menu under component operations:

and the transform tool looks like it takes me through all the steps needed to make this move (simple translate along the principal coordinate axis) - yet nothing happens...

Am I missing a step?  Or is there another better way to do this?