You should really delete your old shaders before saving the .tgo's, Jack. It is quite annoying to have so many unused items load up in each object used, not that I'm complaining mind, you are giving them away.

And yes, even when the extra unused shaders aren't plugged in, they still give errors.
It's easy enough to drag a box around them and delete them all together from the edit menu though so, no big deal.