I'd like to know, once & for all: Are the taps on a CWA MH ballast seperate from each other? Or are they continuous somehow tapped to one another? For example the core side with the 120/208/240/277 etc. volts, are they isolated turns from one another. I burned the 120Volts, are the rest ok or useable?

Well, they're all tapped into the same primary. The taps are all down the road from each other, so if you burnt the 120 tap, you prolly ruined the ballast. That's as good as I can explain it. Sorry man.

Even when the wire for the winding would be separate, a short circuit fault on one winding would mean effective short circuit on all of them.
And as said before, the taps are really taps on a single winding (so the wire goes as 120V winding from the Neutral to the 120V tap, then as 88V winding to the 208V tap, then 32V winding to the 240V tap, then another 240V winding to the 480V tap and so on)

So once there is e.g. just single turn shorted out and that is just close to the 480V, the ballast is ruined even when you would never use that section on the 120V mains, it will form a short circuit secondary (heavily overheating, so the short circuit will spread out to the next and next turns, till either the complete winding burns out, or the fusing blows.)

Oh well, more junk metal for the junkman. Many thanks!

But hey, are the windings made in a way that you can just unwind and remove the bad part ? (if it is in the part you dont use, its absence won't affect the work of the ballast)