Sequencing file processing

I need to process 4 files in a sequence.  I can configure 4 ****ts, 1 ****t
to 
process each of those files but they all process in sequence.  I was 
considering using an orchestration to sequence them.  However, what I
would 
really need to do would be to have an orchestration that somehow activate 
the ****t to process the first file.  Once that ****t is finished with its 
processing, it can send some sort of epoch message to the orchestration
and 
then the orchestration can move on to the next step (activating the next 
****t).  However I am not sure of the following:

1) How to schedule the orchestration.  People has talked about "BizTalk 
Scheduled Task Adapter" but nobody knows where to download it form
anywhere.
1) I have the pipelines and the maps required to transform each file and I

am using regular file adapter to process the files.  How do you coordinate

this kind of processing from within an orchestration.  Would you have to 
enable these ****ts from within the orchestration and disable them once
they 
are done processing?

Any suggestions on accompli****ng this in an elegant way would be greatly 
appreciated.

Thanks.

Waqar Sadiq