How premption work if u are using custom task sequences ?

I am trying to build a model and the need is such that I need to write custom task-sequences.. However if I write a couple of preempting task-sequences it messes up everything. I am using prempt value of 1 which according to the manual should mean that the current task is only stopped and resumed from the milestone task. In actual the multiprocessor never stops but the operator still comes back to it and gets utilized and this messes up model timing..
So the rephrased question is how to ensure that the multiprocessor where the current process is happening stops along with the task sequence if a preempting TS is received by the operator ?

Check your new task is a higher priority than the active one.

yes it may be or may not be.. I have 3 different kinds of tasks on each multiprocessor and they have a priority of 2,1,0. However on a couple of multiprocessors (2 out of 25) all of these task sequences also have a premting value.
Now if a task is being done that has a priority of 2 but a prempting task of priority 0 comes it still should be prempted according to what I need.
However what is happening is that once the pre-empted task is completed the operator comes back to the original task but the multiprocessor has moved ahead since it was never asked to stop. So the operator does the travel task does a stop request finish task (which returns kind of empty since there was no stop object command to resume then gets into utilized state. However the freeopertors command does not work as intended because its written on the processfinish trigger which has already taken place while the operator was away..

Pretty sure they'll need to be higher priority to preempt.

But the preemption itself is happening.. whats not happening is the resumption of the original task

Can you post the example?