Hi Kurt (and Kirill)
I'd just like to say that, following your instructions, I didn't have any serious problem upgrading all my Tuelz to V.2.xx.
I now have a completely different-looking TuelBox and it looks great.
My only difficulty arose when trying to use the v1.0 Upgradez and I got similar error messages as described above. Then I read further down the thread and used the .zip file to upgrade Upgradez. Thereafter, it worked as described. (and Yes! I did back-up my Tuelz v1.xx folder).
In spite of the difficulties I know you are enduring Kurt, you are still at the 'Top of Your Game', when it comes to 'Customer Service'.
You (and Kirill) rock!!
I hope you find a way to deal with your problem shoulder/arm, without going under the 'knife'. I've avoided the 'knife' thus far and am dealing with my 'problem' leg, on a day-to-day basis.
Anyway, this thread is about 'Upgrading' and I'm wandering, so I'll just say that, if you follow the instructions, the Upgradez route is a 'breeze'.