Regarding taking less credit (less than 9) it should be ok if you file petition, stating that

* you are done with your course works
* that you are working in your thesis or design
* there is not any course offered or to be taken 
*  you have some kind of assistantship

I took only 7 credit on Spring 07 and now taking another 7 credits this Fall 07. However, I did file petition both the times and I was told by the ISA officer that is all ok. And hopefully I will be taking just 1 credit for next 2 sem ( just my thesis).

Goodluck!