Thanks for the additional suggestions.
Instead of cutting the tongue, try putting some medical tape over the edge, just to see if it blocks whatever's pressing or rubbing.
I've decided it's not to do with the tongue but a join in the boot that rubs against the skin.
Tape was mentioned earlier, but I didn't try it because I thought it was solved. Unfortunately, it has started happening again. So, on with the tape.
My solution is to buy gel tubes and I wear these over my socks. I find that under the tubes the skin gets sweaty, but the lack of bleeding wounds means that I'm happy with the solution.
I've never been able to keep bandages or pads in place when I skate, though.
I was wearing the gel tubes under my socks with the gel against the skin. After an hour or so of skating, a stinging starts. Off to the hockey box and the gel tube is pushed up and the underlying band-aid or tape is scrunched up. I don't understand how the gel tube gets pushed up because it feels suctioned to the skin. I'll have to try wearing it outside the sock.
This is frustrating because it seems like a penalty for working on bending the knees deeply. I keep trying to simulate what is happening by moving the boot on my foot all sorts of ways while sitting at my desk, but the only thing is the tongue moving back and forth. I am still not tying the top hooks and experimenting with the tightness. Is the hook area too loose or too tight? Just can't find the "sweet spot." I will say that I was having problems with the laces disengaging and falling off - three times in the last couple of weeks.
In terms of the hook tightness/lacing I notice that when they are all laced it feels like the laces are cutting into my ankle. I wear them while working on the computer and try to stretch them into a bend. When I look down all that has happened is the laces have stretched, the boots haven't bent at all.
At least I can skate a hard hour before anything happens. That gets me through a targeted practice and will work in competition and testing. I want to take the pre-preliminary and pre-bronze tests by May and do about three competitions.
Now, where is that roll of black duct tape...