Hi Damion,

Thank you for reporting the crash you have have encountered - I manage to reproduce this and will pass it to our development team for a fix. 

Apart from the actual misbehavior, though, there are few notes to share in regards how to properly work with the dynamic targets and deleting requests from the captured traffic. 

Basically, there are two possible variations when removing some of the requests used for dynamic targets - to delete the source step or the destination step. In the case when the source step is deleted, there is no issue, as the related dynamic target gets also deleted.

The encountered misbehavior occurs when you delete a step, which is used as destination for a dynamic target. In this case the related dynamic target gets in a sort of a default state and you need to edit its destination section entirely in order to continue using it, and avoid the crash as well. (please, check the dynamic-target-deleted-destination-step.png)

If you open the target in edit mode (using the pencil icon on the right side of the row), you will be able to choose the new step to which you need to send the target, choose its type (cookie, query parameter, etc.) and list its name. Then, it will all work as you expect it. 

The need for explicitly set the dynamic target is again related to the specific of load testing and the dynamic targets - please, excuse me for repeating this in almost each my reply, but it turns out to be valid for most of the doubts you have. 

As to the traffic which seems to be not deleted after close-> reopen of Test Studio - I only managed to observe this when reproducing the crash. And in such occasion it is expected that these recent changes applied were not saved. That way the project is left in a stable state before the error appeared. 

I hope these additional details will again help you in your daily work on the load test project. And, do not hesitate to share any further thoughts on the occasion.

Thanks once again.

Regards,
Elena
Progress Telerik