Basically the mining of credits was forced upon cc's wanting to compete in the clash. The format for that competition is fundamentaly flawed, the only way to compete is to fund thousands and thousands of cc passes. Ain't no-one paying for that from thier own pocket.
You built a competition that was not skill based but win by numbers. So to get the numbers people have to come up with inventive ways to get those numbers.
You still insist on rolling it out fortnightly with no change to the format. Ridiculous low value prizes for the effort and credits used.
You created a monster that eventually has proven to eat itself.
You need to pay attention to what the community is asking for and listen more. Get someone on the Facebook page too to answer questions. Your missing valuable customer input there.
The mining of credits was a reaction to your stupid competition set up. Simple.