Kemerton Sliding door adjustment

Having read several topics relating to problems with the sliding door on Boxer panel vans [2012 Kemerton] i have taken the advice of others by fitting a Landrover grab handle on the inside of the sliding door making it easier to open and close, now even wifey can with a bit of effort close the door in one go and secondly by glueing a strip of P seal to the underside of the door opening, hopefully curing not only water coming in when we open the door but also the occasional drip when the door is closed, as Weymouth is blessed with dry weather at the moment Iv'e only been able to test it with a hosepipe but it definitely seems to of made a difference. The one thing that Iv'e not been able to do is adjust the door so that it sits flush with the side of the van when closed, the adjustment on the bottom of the door looks easy to adjust but can not work out how to adjust the top of the door, at the moment the top of the leading edge needs to be pushed away fom the van and the top of the trailing edge needs to be pulled in closer to the van. I have searched the internet and this forum but can not see any reference to this, so any advice on this would be much appreciated.
kind regards
Batch

Sliding door fit is Peugeot problem