Problem with WO 48mm T-mount -SOLVED

[Felias]

Hello. Apologies that my first post is a call for help, but after searching the web in vain I thought that someone here might have an answer to my question. I bought a couple of weeks ago a WO Z61 with flattener from FLO. The telescope seems fine, but I can't attach my camera to the WO 48 mm mount also provided by FLO. For some reason, it won't screw into the body of my camera (Canon 77D), it barely fits in and it definitely does not rotate to click into position, so the camera falls as soon as I hold it by the T-ring. The T-ring is the following:

https://www.firstlightoptics.com/adapters/william-optics-dslr-m48-ring-adapter.html

Now, they have been brilliant at FLO and they have sent me a replacement T-ring. But it doesn't work either, I have exactly the same problem. They have now offered to send me a generic ring of their own brand to try before I return the WO ones, which is amazing but will take a few days. I was just wondering if I am being stupid and doing something wrong, so before the new ring arrives I though I'd ask. Am I overlooking something? Is there anything in the WO T-rings that would prevent them from attaching to a cropped-sensor camera? I have noticed that the ring has a white dot, which is normally used for mirrorless cameras or EF-M lenses in Canon, is that relevant? There is also a little screw on the sides that is positioned differently as compared to those in my lenses; I don't want to tamper with it because I'll have to return these T-rings, but I wonder if that's the cause?

Any help will be much appreciated. Thank you!

Edited December 7, 2020 by Felias

[Felias]

I have solved the problem, so I leave a reply here in case anyone else has the same issue in the future and looks for an answer in the forums, as I did. After FLO sent me an Astro Essentials T-mount that I could fit into the bayonet of the D77, I had a closer look at the two defective WO mounts. The only difference with the AE mount that I could see was that in the latter the little screw I mentioned above was protruding less. So I decided to tamper with the WO mount and screw it a bit in. It took a few turns, but after that I could rotate the mount and lock it into position. Problem solved!

I am very puzzled that no one seems to have met this problem before (or maybe the solution was so obvious that no one has bothered to report it). I even wrote to WO, and they replied that they had never heard of a defective T-ring. After my feedback they said that their QC team will tighten those screws in all the T-rings, so I assume that they really can be an issue and it wasn't just me. Perhaps it only happens with the D77, but in any case it's solved and now I just need to wait for the weather to improve so that I can try the new Z61. I may be a long wait though...