Most other modules, if it says you can only have a certain number on your ship, when trying to build one more the game counts how many installed and uninstalled modules you have.

Not so for Lazuli Mind Controllers. I currently have four uninstalled ones on my ship. It will only let me install three at a time, which is good. But it should probably refuse to let you build the fourth one at all, if you have three already.

If one is broke it normally lets you install another one anyways but then you can still have so many installed on your ship at once.

Since they aren't my best non-standard weapons, I'd built them and uninstalled them one time - they were not in need of repair. Just had three uninstalled ones, and was able to build a fourth.

I could only have three installed and active at a time, which is correct - but I think it may be a bug that you can build more than 3 period on your ship.