Hi:
This does not seem like a stored process question, (even if you want to make a stored process into a Data Integration Studio job) because using a DO loop and using a %DO loop are vastly different topics.
If you want to apply a (working) set of processes/analyses to multiple data sources, I believe you would not use a simple DATA step Do loop, but would instead use SAS Macro program and processing and a macro %DO loop. This might change the program or process flow that you are building in SAS Data Integration Studio.
Your best bet for help with this question might be to contact Tech Support.
cynthia