For some reasons new members are ending up with hundreds of thousands of credits. Even when I recalculate events it doesn't make a difference. These are members that are not active and have never posted anything.
If it has no entries that would explain this, then this is not caused by vBCredits but instead another modification that adds to vBCredits' points table but does not report the credits given.
I've just checked - the credits mod has credits called 'Points' and the shop mod has credits called 'Simoleons'. It's the latter that is showing too many credits, but I'm not sure how to modify the mod to stop this from happening.
It appears from the log that members are receiving interest 'payments' from the day they were registered, but I've disabled the interest activity section from Activity Amounts Configuration.
Have you also turned off the bank feature in vBShop? If it doesn't show up in vBCredits' transaction log, but it does in vBShop's transaction log, that means it's the bank feature in vBShop, not vBCredits, whose interest is causing the problem.