I found some time today to play the game again. I expected my mod to be broken. It turned out 1.1.0 still works with Factorio 14.21 indeed.
So I just updated the mod details to be compatible with the ingame mod-manager.
I'm also going to use this page as the official mod home now. So only this place will be kept up to date. I'm copying all texts to here now and will work on the formatting the coming hours.
So yeah, 1.1.0 still works with a manual install. But 1.2.0 is the latest fully compatible version.