I want to pawn 3 or 4 CWs, but I don't seem to understand how the process works. When I click to pawn the item, it just redirects to the buy CSC page. Can anyone please explain?

Are you on this page: LINK?

Yes. But when I select a CW to sell, it opens the 'Buy CSC' page. Do I just enter my credit card number somehow and it credits to my card instead of just giving csc?

No, it shouldn't be asking you to pay money to sell a CW. This sounds like a bug or a glitch to be honest.

Should I just file a ticket?

You could, maybe they can see exactly what is happening.

I'll file a ticket, thank you!