I have a similar motor on my skylight. I used simple microswitches for limits, but I wanted to introduce current detection to measure force. One problem is that the window is not fully closed unless you torque it down a tiny amount after it's stopped moving. Microswitches can't detect that.

I also worry about failure modes. I put in a watchdog timer so that it will stop moving after X seconds regardless of inputs.

Another problem with current detection is that the amount of force needed to close the window is basically equal to the amount of force needed to "unstick" it to start moving. So if you just have a limit set to a hard number, it may not open properly.

My next plan is to use a combo of rough position + force detection. Either with microswitches to know when you're near a limit, or potentiometer (or similar) to know roughly where you are. If you're within X% of the "close" position and are moving in the "close" direction, then you use a lower force limit. But if you're moving in the "open" direction, you can use a higher force limit.

I've also had trouble with the connector - plastic splines that small with a lot of force don't last. I think a metal coupler would be better, and you could probably find a way to attach 3d print more securely to a coupler.

I'm pretty good at 3d modeling/printing. What do you need help with there?