I have a number of Shopping Cart Rules with several different Actions but also I have one Catalog Price Rule giving 40% off everything.
Now while this 40% Sale is on I don´t want any other Rules to be processed.
But somehow this won´t work. Is this because some are Shopping Cart Rules and one is the Catalog Price Rule?
I set "Stop Further Rules processing" to Yes on both.
I post a solution here: https://stackoverflow.com/questions/11718504/catalog-price-rule-vs-shopping-cart-rule/34099115#34099115 or here: Disable catalog price rule on coupon code
Catalog rules and Shopping cart rules are treated separately, so they can stop in same group but bot between those two types. So what to do to prevent them stacking?
The idea came from Marshall Thornton' blog: http://www.magentotips.info/modules/catalog-shopping-cart-pricing-rules-stacking/#.VmIev98rKV4
Basicaly you need to extend Mage_SalesRule_Model_Validator::process() method
