Hi Finn,
I’m sorry to hear you’re not satisfied with your purchase from optics-pro.com. You’re correct, the Lacerta upgrade kit does not include the set screw, mounting screws, or Teflon block. These parts must be transferred from the stock focuser to the upgrade kit. We highlight that in a red box in our product description to prevent bad surprises, though I’m not sure if optics-pro.com includes the same note on theirs.
I’m also surprised to hear that your stock focuser felt stronger. The upgrade kit doesn’t change the focuser’s load capacity, it simply adds dual-speed functionality. The Synta-made focusers (like the one on your StarSense Dobsonian) have a capacity of about 4 lb max. To achieve that without slippage, the focuser’s tension needs to be adjusted. Since you mentioned the set screw, I suspect you may have already tried this, but if not, it’s worth checking. Your 31mm Nagler weighs around 2.2 lb, and a binoviewer setup should be roughly the same, so the focuser should handle that load once tensioned.
Unfortunately, since the kit wasn’t purchased from us, we can’t propose you a return or exchange. It also seems like the end of your review was cut off, if you’d like to share the rest, we’d be happy to add it for completeness. You can send it to us by email. And if there’s any way we can assist further, please don’t hesitate to reach out!
-David