I'm trying to generate a NORMAL environment world which has glowstone as an Ore. Unfortunately, the glowstone doesn't emit any light until it is first affected by a nearby light update. Is this a TC issue?

Yes, TC just makes the vanilla bug more visible.

Actually, seems upgrading to dev version fixed it. I thought it hadn't, but after I took the time to write this message and checked back it was fine. Must have been still calculating.

ACTUALLY, maybe some of them work, some of them don't. But arbitrary lighting issues are more likely to be vanilla...