Markarian's Chain

It holds, I use it with a counterweight so it doesn't tip over at steep angles.
And the slew rate during navigation is reduced, otherwise the mount can't lift the telescope in some cases.
But for guiding, there are absolutely no problems at all.

The telescope is generally fine, with no play, flex at the focuser, or other common beginner issues. My unit came with a damaged secondary mirror (scratched in one spot), so I'll be replacing it (fortunately, there are similarly sized replacements available on AliExpress). There's also the issue that I still haven't been able to collimate it properly (I haven't succeeded using the OCAL tool I own), but that's due to my own lack of experience and not having the right tools for this type of telescope.

Thank you for the detailed answer. I understand that, overall, a more robust mount is needed. Regarding collimation, I can collimate my Sharpstar 130 with a laser collimator in about 5 minutes.
Perhaps the 200mm model has some specific characteristics. In any case, the speed of this series is impressive. Clear skies!

I'm currently using a laser collimator to get it to a state where I can shoot (but far from perfect, judging by the aberration inspector).
After OCAL, I have a strong tilt, but at least it's easy to set the correct secondary mirror height and rotation along the x-axis.
For now, I think my problem is specifically with OCAL.

This is roughly what a calibrated flat looks like through ocal
https://imgur.com/a/OPepajC
And such a "perfect" calibration produces strong tilt on a real camera

In my opinion, the issue isn't calibration.
Fighting camera tilt is very difficult and, I think, unnecessary. I've also tried everything—adjusting the screws on the ZWO 2600, trying to realign the focuser assembly.

Especially since the camera tilt problem affects the stars. At least that's how it is for me, and elongated stars are easily corrected in any program like Siril or Pix.

In my opinion, the issue isn't calibration.
Fighting camera tilt is very difficult and, I think, unnecessary. I've also tried everything—adjusting the screws on the ZWO 2600, trying to realign the focusing unit.

Especially since the camera tilt problem affects the stars. At least that's how it is for me, and elongated stars are easily corrected in any program like Siril or Pix.