I am not able to reproduce the scrollbar problem. I have created a new application and loaded the above xml file, but no matter how fast I drag the horizontal scrollbar back and forth it doesn't produce any exceptions. Is it possible to send me an application demonstrating this bug, maybe it is somehow related to your settings? Also, what regional settings do you use?

Regarding the slow import, it is related to the number of imported items and resources as well as the interval currently displayed in the view. If the interval is too big, the control needs to create the visuals for all items inside this interval and this will be slow. We are currently working on some optimizations but we do not have a stable version yet.

Kind regards,
Meppy