How did you make your medals appear under your post? Is it auto when I play so many games or something else? What karma anyway? How do I earn it? Yes, I know alot of NewBie questions.
I forget the exact UI wording, but you just need to edit the Metaverse character you want to use to show your medals. I only have the one character, so I'm not sure how the UI appears when you have more. The medals change slowly as you post more MV games. This thread has a bunch of talk about the medals, starting with some basics about how you earn them.
Karma is a Stardock forums thing, not necessarily directly related to GC2. You can click the little thumbs-up button to open a pop-up that lets you give "karma" to a post you appreciate, and enter a brief explanation about why. As to "earning" the site karma, it is more or less a fusion of popularity contest and performance rating. Some people seem to give karma because they just found a post fun to read or they are on some empire-related bandwagon, others give karma when they see good answers to their game questions, and others do both.