Creating custom indexes

Hope this is an easy one to resolve. 

I've been looking at the improvements made with SP2 and the added flexibility we now have for creating custom indexes. I for some reason don't get it to work however. My search keeps using the cqTags index. Even when I delete the  cqTags index! I make sure I have reindexed my custom index. But for some reason it doesn't get picked up.

So here is the question:

1) How do I make sure an index is removed?

2) How can I see that a custom index is even considered when querying?

Many thanks