So I was able to install the advanced power monitor by following the instructions given by darbax (in conjunction with what I've written above, which I had to do again after being unable to install it the first time).

However, it doesn't show any of the old information (battery life, etc). Now it just says "Start APMD" abd "Settings." After hitting the first button, it just goes grey, and hitting the "Setting" one doesn't do anything.

Hoping someone out there knows what is going on!