Did you get an automated response with a ticket number? If not, check any spam blocking you may have. You may also try using a different email address or posting a ticket directly at the support site.

If you did get an automated response, do bear in mind that support works standard office hours, so they will only be able to address tickets on weekdays.

How do you mean? If you've already registered the game to your account, doing it again wouldn't have any effect. If it was a used copy and was already registered by someone else though, you won't be able to register it at all.

Serials should be entered exactly as they're printed. Just to be sure, older copies of the game may have multiple serials with them; if you have a Dread Lords serial beginning with GC2- then it's only for unlocking the collector's edition content, not for the metaverse or updates. If you have GC2 Gold it has a different format and that potential issue doesn't apply.

In any case, if you have a support ticket number from the autoresponse, post it here and I'll have them pull it up specifically in the morning and get you a better response.