SWIM plugged a 9V DC power supply into a 16VAC Blackstar pedal and it no longer works. The tube no longer glows. Would anyone be kind enough to inform me how bad SWIM F'ed up the pedal. Thank you!
MARTY FRIEDMAN--"It’s a lot easier to be technical than it is stylized; it really is... But I think it’s a lot more rare to have someone who’s really got their own sound because that’s something you can’t practice."
The original power supply doesn't light it up?

If the polarity was the same as your Blackstar pedal there should be no issue.
If it was reversed you probably fried something inside.
There's usually internal protection around the power supply which is probably blown and has to be looked at my repair tech. See if you can get the schem from Blackstar to trace it over or just ask them and ask them to look at it.
I did same thing to my Sansamp TRI-OD and they fixed it for $60.
The original P/S is AC and has no polarity. Since the pedal is capable of handling + and - voltage (it's AC) with peaks of ~12V (8V * 1.4) in either direction, I would not expect the 9VDC power supply to damage anything. But it's still possible that it caused a problem. The question remains.... have you tried the correct supply?
A friend of mine hooked up one of my AC output multi-effects adapters to his DC input pedal. It did not work and the pedal fried. Don't mess with power adapters if you don't know what you are doing. Try the correct power supply (order it if you have to) and see if the pedal works again. Generally it's best to supply what the pedal calls for and not try anything else. Some pedals deal with lower voltages but AC to DC current is not part of that versatility.