I can give some update on this issue. The "repositioning" of the floating contacts occurs when my home computer looses connection (and MSN signs in again!). There is no position change of the floating contacts when simply signing in to the already active desktop (meaning MSN was already running).
I have an idea about how to solve this, but I don't know how complicated it would be to implement that. Make floating contact positions relative to their nearest screen edge. That is, for contacts in the, let's say, lower right corner, their position would be relative to the lower and the right edge of the screen. All of this would only apply up to a certain distance from the edge, so that centered contacts are not affected. Next thing would be the "real time" update... maybe it is possible to do this position checking every time the desktop is redrawn (which should also be the case when someone signs in using RDP). That way, the floating contacts of the e.g. lower right corner reappear on their "correct" position if the screen is smaller than before... and also go back to their original position once the screen size goes back to normal... if it works that way, that is.
I hope this was understandable and gives you some clue as to how to improve the system
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