This bug was known when I decided to implement it. Basically TTT randomly picks the traitors at the start of the round using a percentage of 0.25 however I have capped the maximum amount if traitors at 9. So when you purchase traitor round then it simply hooks the start of the round and makes you a traitor.
But because it had already assigned you a type the game scores your performance based of the initial type you were spawned as. So if you were picked as an innocent then purchased traitor it would award you as if you were innocent.
Karma is currently half disabled while I work on it. It still displays karma but it gets reset every round if you don't rdm / damage anyone this is called a clean round and re bases your karma back too 1000. I am currently deciding if I should completely remove karma and just use the point scoring system so if you rdm you lose a set amount of points if you do the right thing then you are awarded points.
Then the points you gain will unlock more credit for you to use in the traitor / detective menus for example 25 points = 1 credit. Point-Shop credits will still be awarded based on time played.
Also CS:S and De map's have been removed because `Kayne told me nobody had them. You need at least one source game to play Garrys Mod properly and CS:S has all the maps and textures, some maps rarely include Portal 2 or Hl2 textures.