Michael, please refer to
http://www.oxwall.org/forum/topic/23395 .
User Credits plugin is now connected to User Roles. If user role allows certain action, then credits will be ignored. So if you would like users to loose credits for example for "contact me", you will need to uncheck the box for this action in user role's permissions.
I am not sure how "Hot list" and other plugins you have mentioned work, so I can't tell whether they add permissions to user roles. Please check this in Admin Panel >> Privacy&Permissions >> Roles. If they don't add such actions, then it is worth checking with plugins' developers.