Once fitted, this fitting works well allowing the ZWO EAF to be attached to a 200mm TS Photon. The attachment process was tricky due to tight tolerances on the inside diameter of the fitting. I removed some ougness in the machining or 3D printing by sanding. Then fitting the assembly was relatively easy once I heated it gently with a hair dryer. There were no instructions, which would have saved me the unnecessary task of completely dismantling the focusser. Once the four grub screws were removed attachng the focussuser to the plate on the OTA, it should be possible to fit the attachment to the focuser without further disassembly. The bottom line though is it works well.

I didn't realise this based on the photos here, but you need to completely disassemble your focuser to install this bracket. Grubscrews for the control knobs need to be undone, knobs removed, remove the tension and locking screw and the little plastic cover for the fine control side, then remove the shaft and fine control mechanism (this causes the focuser barrel to fall out). This leaves you with a hollow focuser and makes it possible to install this bracket.
The bracket is a TIGHT fit. I had to take a small hammer and tap it on (wincing the whole time, worried it might damage the scope although I was not overly rough). It was not easy to get it on far enough to line up with the control shaft and motor. Now that it's all on however, it should hold things nicely and stay put.
Only reason for the downgrade from 5 to 4 is the difficulty of installation and the fragility of the plastic. I broke one part of it by over-tightening a screw (marine mechanic, not used to doing spanner work on fragile things!) but thankfully it works just fine despite that. So I would recommend getting things nipped up until there is no more play and then stop, as it seems to be deceptive and feels like it needs to tighten more, and then it goes pop out of nowhere!