To tighten the M4x16 screw you need an M4 threaded insert
Build for this Kopp Universal Dimmer (LED 3-100 watts):
https://www.amazon.de/gp/product/B07ZTKSGR7/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
In my case, the original dimmer switch does not want to turn because it is only connected to the rotary pin with a wire
The print-file is updated, so you need no support :)