I had a question, at the London roadshow (8th June), which I wasn’t sure if I could answer reliably, so I promised to blog the answer.
The question: “Can I run selected (with mouse) tasks and transforms from inside the SQL Server Integration Services package designer?”
The answer I have is, for transforms, no you can’t. For tasks you can – or at least just about. You can select single or multiple tasks and then right mouse click and choose to 'disable' the selected task(s) – whereupon they appear greyed out. Then when the package runs, those disabled tasks are not included in the run.
You can also right-click on a task in the control-flow and select "Execute Task" exactly as you could for DTS.
Is this not what the person was asking? If you want to run more than 1 task then you're correct, the only option is to disable all the other components. Perhaps a "Run from here" option on the right-click context menu would help.
Certainly you can't for data-flow components and it makes sense if you think about it. After all, what data would the component carry out its operation on and where would it put it afterwards. Don't underestimate the value of breakpoints in a data-flow however - this is the closest you can get to testing a cmponent in isolation.