I tested this and I see what you mean now. The problem is that the ‘center’ link automatically centers the map to show all of the POIs. It doesn’t consider the original center and zoom.
For individual maps (as opposed to mashups) it would be better if ‘center’ just reset the map back to its original cneter/zoom values. I’ll see if I can implement that for beta 2.38.6.
Until then, you may want to remove the ‘center’ link to prevent the behavior.
For mashups, like the widget, it will need to continue to automatically center, since the POIs could come from many different maps.