I am using the skin below. I wanted to see how it looked if I added another forum column for information. I set the new column to 180px, tried content and decided I didn't like it. So I removed it, reset the new column to zero and saved. The forum columns did not return to their original width (see the red line) - essentially the leftmost column remained "scrunched" and the rightmost column expanded to replace the removed test column. How can I get the right column to it's original size? (I thought about re-installing the skin but my question there is any of my original "stuff" altered. I have a copy of my edited CSS and can re-insert it but how about everything else?).

reinstalling the theme won;t change anything.
But 1 question before you do a reinstall .. in your forum widgets ... on the right side were you entered 0 pixels ... are there any widget boxes in the 3rd column?

you must make sure the right column is empty and set at 0 pixels