Greetings all - There was something misconfigured on the server which was causing some Entrenchment installs to not work. If you fall into this category (and I imagine you know who you are) please do the following:
1) In Impulse click the Stardock logo (orb) in the upper-left and select Check for Updates (or restart Impulse).
2) Install Entrenchment normally. If you have an install in progress and don't want to take any chances, Cancel it and start over.
My apologies for the issues.