5.22 refuses to activate online, offline server now down as well. What to do?

I am on XP and according to the Sandboxie website, v5.22 is the latest version I can use...

Since Sophos took over, I have never once been able to activate Sandboxie online, always receiving the error...
  Product activation failed:
  An error occurred in the secure channel support [err 12157 by 14]
  If you need to activate Sandboxie on a computer that does not have internet access, please see the Sandboxie licensing FAQ for information about Offlice Activation.

I have got round this by doing offline activation, but now even that server seems to be offline, giving a 502 error. See...

Given that Sandboxie is now freeware, please can you provide me with either a link to a patch that removes the activation requirement, or an activation code that does not expire?

Thank you.