Only start a process when the last process in the queue ends

Hello!

i have a question and hope for your help!

I have a process with 2 subprocesses. Now i have a problem with the first subprocess.

In the first subprocess Task 1 should only start when Task 4 is completed. Task 2 should start wen Task 1 is completed. And Task 3 should start when Task 2 ends and Task 4 should start when Task 3 ends.

Currently my problem is that when i start the simulation, due to the duration of the task Task one is start 124 times but Task 3 started only 73 times.

I need that task 1 to 4 have been always processed the same time.

Do you have any ideas or is that not possible?

Thanks in advance!