Making them player usable is pretty easy (open up data\subsystems\flagships\weapons\BlackholeTest.txt and add DefaultUnlock to the list of tags), but adding a research topic for them is a lot more complicated, and can't really be explained in a comment. You could look at one of the weapons already on the research tree, copy how it does it, and apply it to the weapon called BlackholeTest though.

Interesting. Did I really give those to the remnants? It'd make sense, I suppose :) I don't remember it being intentional, though.

They're the weapon for Ancient Planetary Cannons, to make them a little more impressive/interesting than just a 'free' normal planetary cannon. They fire a shell which has a massive area of effect (often hitting every support ship in the entire fleet simultaneously), a good chunk of damage, and also a significant kinetic force towards wherever the shell hit. Also, I'm rather proud of the visual special effects, which took ages to get right.

If you want to use them on your own ships, it should be fairly trivial to change the files to make them a player ship weapon as well.

Hmm... I admit I didn't even think to check that. Thanks for the report. I've logged it here, and eventually (maybe this weekend) I'll try and fix it.
https://github.com/darloth/SR2-BuildingAssortment/issues/1

Hmm... I admit I didn't even think to check that. Thanks for the report.

Was playing around with this: found that Nylli Motherships can build Habitat Belts... around themselves (provided that they have the means to acquire Ore). This does nothing. It'd certainly be neat if the Nyllia had a way to build up their planets with Ore, but that particular implementation needs fixing.

The cloning Center is in a way better spot in the research tree now, nice!

Finally updated for new tech tree. I'm surprised nobody out of the silent majority complained, but if you were silently hoping for an update here it is. (I would have done it much earlier if anyone actually asked, though - just forgot about it for a while :) )

I love the forges generating ore, and the Habitat belt, very well done, and a neat use of existing mechanics. The refineries also are cool to use as they allow basically squeezing research/influence/production worlds with tons of metropoli. Again great work Darloth.