Hey Bronto,
Try downloading the latest launcher from the forums and put it on your desktop.
Be sure to have a correct path to your steam mount and blade warband folder.
Make sure your Virus scanner doesn't see it as a false positive, and it's allowed through your firewall.
Try unchecking WSE2 box and press repair while updating. If it works, click WSE and try again
Lemme know if it works or not, if not, I'll try to find more solutions ;)