Did you also try to start with the 2.53 SX File an generate the key? They had an issue with 2.6 at the beginning.. should be already fixed with 2.61.. but perhaps, give it a try..
You can generate the license on your PC using the sx license website, which is down at the moment..
But do you know, what URL or IP or Web or Cloud-Service is implemented in SX, if you activate it directly on the switch online?
is it verified, that the license check in SX try to get the URL, which is down? Sure, you cannot generate one on the offline Website.. but perhaps they build the check from the switch to another endpoint..
I hate when that happens, you just get out of shower n need to drop bombs. Guess I could of just used the shower and waffle stomped them logs into the drain.