I'm a newbie to this site and DTS as well, but in the past I have had a similar problem where I had a process that needed to know when a group of separate processes had completed.
In other words, when processes 1-9 had all completed successfully, process 10 (which used output data from 1-9) was free to run.
The way I handled that was to have 1-9 write entries to a table when they completed. The table had a trigger that fired on inserts which checked the table to see if all of the processes had written entries. If all of the processes had finished (and thereby written a row to the table) then it fired off process 10.
Perhaps this might help with your situation?