i too got this, on top of a bung update (an unrelated issue that occured at the same time).
it also occurs with SupCom not linking to a *.dll of GPGNet's. i spoke to Nakor, of Stardock via IRC a few days ago and he linked my to; http://sd.stardock.com/remove227.zip which fixed it for me, but i was running the beta 2 engine on beta 1 data so i had to re-download the whole lot again.
if that doesn't fix it, it turns out you've also got my, presumedly, unrelated error. so you'll have to completely uninstall DG and delete all traces of it except for *.impulse archive files and then re-download.
