1) When you choose a "commercial" civ are you not supposed to get an extra gold in the city square? This did not happen for me in my first attempt (English) so I am wondering exactly how do you get the extra gold? I see almost no difference from playing a non-commercial civ so far (lots of corruption).
2) How do you take a picture of your screen for validation purposes? PrintScrn certainly doesn't work for me.
the bonus commerce that you get is after you reach a certain size. Check your larger cities, especially those above 12, you should see it.
I believe the screenshot question.... well someone with a program can help you more than me (specific util), but, there are programs out there (some free) that take screenshots when you press a key. Search for screenshot utility or something along that line.
One thing you might want to try. You said the print screen button didn't work? did you try switching to a picture utility and pasting?
When you press Print Screen it copys the screen to your clipboard, you can then paste it into any picture editor (such as paint).
One thing though. Make sure you highlight a few characters and press ctrl-c to copy them to the clipboard. A screen shot takes up alot of memory, and it's good to keep the clipboard as small as possible, to keep your computer running as smooth as possible.