I always found this site useful for whacky connection string help:

http://www.connectionstrings.com/teradata

The annoying part about those "?" parameters is that if you have lots of them you can't easily see which parameter they map to in your SSRS parameter list which makes it easy to make a mistake and hard to debug. At least They work in order!

I know what you did, you fell back on that failsafe way of getting rid of IT gremlins, turn it off and on again!