Cannot login to the game or to this forum

[Yardem Hane_XBL]

I can post from this PC because I am still logged in and have a valid cookie. However, if I try to login on a different PC, or in the game, it fails with various errors.
Most often, I see "504 Gateway Time-out".

This means I can't play the game at all.

XBox have no issues with authentication, this seems to be a problem with SDS servers, or their integration to XBox.