It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

I know this should be obvious, but it helps a lot if a person reads the manual. I purchases Space Rangers 2 a few years ago. I purchased it again from GOG to get a copy free of DRM. The first copy I had used the dreaded StarForce DRM! Anyway, I thought I had read the manual as I read the one that came with the physical game I purchased years ago. That manual was only 15 pages long. To my surprise the manual that comes with the GOG version is 102 pages long! It explains a lot of subtleties in the game that I didn't know.

Curiously, it seems the pdf manual that is installed with the game is a 11 MB file and the one downloaded as an extra is a 15 MB file, yet they seem to be identical when you open the files and read them. Go figure.