Disclaimer: I am NOT a developer, nor the maintainer, which is why this is in General. I am making this thread at John Kirk's(CarbonROM Dev and maintainer) request.
Let's get to the point, Carbon is back on Manta! Starting with 5/31, Nightlies will be built for the manta. There is already a test build released by him, link is here.
Changelog Page(GDocs and Gerrit): https://carbonrom.org/changes/
Current bugs(FROM Nightly 5/31)
Carbon Fibers is borked, certain things are in the wrong spot, or are invisible
Microphone doesn't work
You can send bugs/logs to John Kirk directly(email is in the About Carbon section in the ROM). I'll post issues here as well as people report them.