While the OP's problem appears to be solved, I'd still like to continue the "mirror props within Poser" issue.

We have various, even contradictionary, reports on the "trick" of negative scaling: For some users it works, for others it doesn't, even if they have the same version of Poser.
This intrigues me.

I'd like to find out what causes this (maybe an issue of the respective SRs installed? I'm still on PP2014 10.03.26510)
However, I installed Poser 7 Pro today, and it doesn't work there either.

I mean, it could be a great feature: to be able to mirror a prop "on-the-fly" (without the need of exporting - then using another program - importing - finding out that the external program messed up something - redo the procedure, etc., ad nauseum).

So maybe we could find out what makes this "not" work, and how to fix it.
Anybody else interested?

Thank you.

-Peter-