Q:

SSRS 3.0 Report Map + Map Report Part change position when run

I have created a simple geographic map using Report Builder 3.0. 
In order to have a sub-section of the map to zoom in on, I published a report part from a different report and included it on my map like so:

However  when the report is run it moves the report part outside of the map like this:

The print view shows a things back as I would expect.

The eventual target for this map will be as a SharePoint PerformancePoint Services Report.
Does anyone know why I am experiencing this odd behaviour?

A:

From the MSDN article about report rendering
Overlapping Report Items
Overlapping report items are not supported in HTML, MHTML, Word, Excel, in Preview, or the Report Viewer. If overlapping items exist, they are moved. The following rules are applied to overlapping report items:
If the vertical overlap of report items is greater, one of the overlapping items is moved to the right. The left-most item remains where it is positioned.
If the horizontal overlap of report items is greater, one of the overlapping items is moved down. The top-most item remains where it is positioned.
If the vertical and horizontal overlap is equal, one of the overlapping items is moved to the right. The left-most item remains where it is positioned.
If an item must be moved to correct overlapping, adjacent report items move down and/or to the right to maintain a minimum amount of spacing between the item and the report items that end above it and/or to the left of it. For example, suppose two report items overlap vertically and a third report item is 2 inches to the right of them. When the overlapping report item is moved to the right, the third report item moves to the right as well in order to maintain the 2 inches between itself and the report item to its left. 
Overlapping report items are supported in hard page-break formats, including print.
See also.

