Here are some suggestions on your issues:
(column width and overlapping)
When RadGrid scrolling is enabled and no width is specified for the columns or the MasterTableView, by default RadGrid accommodates all columns so that they are all visible in the control's available space. In order to change this, you can do one of the following:
Set some large Width for the MasterTableView, e.g.
Set some width for all columns, e.g.
Set some widths for each column programmatically.
(popup edit form positioning)
I cannot reproduce this problem neither in your application, nor in a test page of mine. Am I missing something?
the Telerik team
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