As to your questions:
1. I am afraid we cannot suggest such an event. You can refer to our Drag and Drop examples for a further reference.
2. You can check the definition and usage of HideDropPositionFeedbackPresenter
in the mentioned help article.
3. When RadGridView is sorted, then the order of the items cannot be changed with a simple drag and drop as it should remain ordered as defined through a SortDescriptor. Do you experience a different problem? If so, may I ask you to open a new support ticket on the matter providing some more details on the exact case?
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