Basically not playable anymore

Good evening,
since a few weeks I got several issues playing hots on Mac OS. First of all its not possible for me to run the game in my settings I had the last years (was using ~ultra mostly). If I don’t use “Low” the game has currently just a few frames per second. Using low though still causes an issue which feels like lags. Every ~1-2 seconds the game lags for a millisecond. And this happens during the whole game continuously. It feels like a loop. This is independent of internet connection or cpu/gpu usage.
In addition there is an issue with resolution and/or windowed/fullscreen mode. If I switch between windowed/fullscreen or change my graphics settings I suddenly hav a cursor which is 50% smaller and the distance of the mouse movement is doubled. I assume this is a resolution issue as I remember that there was a similar bug on hots a few years ago on retina macbooks.