Hello,
I tested this a couple times. I had the username of Bodegus when I first registered Demigod. I have since changed to Bodegus_BL to reflect a clan association. I cannot automatically update Demigod, when I click "refresh" on the game queue to check for an update, I get a login failed message at the bottom of impulse, though I can login through the impulse login in the community tab with my new username (and it is displayed in multiplaer).
I changed my name back to Bodegus and could isntall the patch