I had the answer to one question here: https://community.nintex.com/message/70240-re-returning-to-a-flexi-task-after-its-been-rejected?commentID=70240&et=watches.email.thread#comment-70240
Now what I need to do is to kick off the Flexi-task again after the user has resubmitted the form after it's initial rejection. I've put a 'Wait for item update' action in but don't know what Field or value to put in to tip the workflow off that the form has ben submitted? 
OK first of all I think you need a third state (in the middle of the two you have) where your *** STAGE THREE *** flexi task is. you can use change state on approval branch of your first flexi task to move to the middle branch. and again use the change state action after the wait for item update action. this way you don't have to duplicate your *** STAGE THREE *** flexi task
Secondly... do you have a status field or similar that you use to track the progress of your item (submitted/awaiting approval/approved/rejected) etc? If you do, you could set form status to "rejected" on rejection and then when the user submits the changes have the form update the status to "submitted" again. if you do that your wait for item update could evaluate the status field and wait for the item to be updated to "submitted".
does that make sense?
Cheers. I don't have a status field but I do a filed which I use to change the Form View after submission. It's set to 0 or 1 but I guess I could add a 2 and use that as 'Wait for Item update' action? Where would the place to add the Set field value action in that case?
ok how do you set it to 0 or 1 currently?
have you customised your form using nintex or is it InfoPath or standard SharePoint form?
Hi. It's set to 0 and I'm using InfoPath.
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