I am just getting using QTO manager more an one thing that bugs me each time I use it is that in the assign pay item command you cannot use crossing window selections for multiple items. To assign payitems to multiple objects you have to select the objects first than go to the QTO manger and select assign pay item.
then the command line will come up with
Just press enter and payitems will be assigned to all of the objects you had selected.
To check that the items were assigned if you have roll over tool tips turned on move over the object and the payitem appears in the tooltip.
otherwise in the QTO manager select the payitem from your list of items and right click and choose select items with payitem