Job Scheduler - Serial Execution

For years we used a Delphi scheduler that I wrote which no longer wants to run on Win 8. I converted everything to Windows Job Scheduler and it all works great except:

The first job in the task waits until all users are out of the database files before allowing the remainder of the task to continue. If they all leave at closing time the scheduler does a great job and waits for the execution of each step before continuing.

If they leave a few minutes late it seems that the scheduler releases all the jobs and the backup and DB maintenance jobs run over each other.

I don't really understand why.

Thanks
TuckerJ