Not sure if you know about this but I am getting a problem when running an UltraListView across two monitors and then try to resize a column on the right hand monitor - it snaps to about 10 px wide as soon as you release the mouse.  The only way to get it back to a decent size is to get it back on the left monitor (somehow) and then resize it.

I have attached a simple sample application where you can test this if you have a dual monitor environment.