Constrain prop the right way?

I went to search some tool to save some weird inventions I made and I came across this

Is the guy answering correct? I basically just used weld and some nails to put together the darn contraption and I don’t want it to be destroyed with the saving tool. I would like to know if there is any way to actually put two props and make it combined so that the tool would save it.

Use the advanced duplicator, it’s fine.

o_o I honestly did not see the advance duplicator could do that. Thanks.

No worries my friend.