There is the possibility to set that:
When you start an application A (.exe) is another specific application B (.exe) already present "for this reason" the application B can be auto-modified (priority, affinity, etc.) and when closed application A, does the previous activity for application B return as before?
I was hoping it could be done with watchdog or something else.
No, I'm sorry, but that's outside the current capabilities of Process Lasso.