Thanks. I did happen to see that today but since creating this post I took a stab at fixing it to compile in 3.0 and was successful. The only bug I found, in limited testing, was that I couldn't save templates. Couldn't figure out how to fix that one. Maybe I'll take a look at what coomsie did and see if he got it working.
I also dismantled the widget somewhat to create a separate widget just for measuring with a line. It's certainly sloppy/not ideal since this is new to me but it looks like it'll work...which is good since there are no alternatives out there.