You can do this through the Sysmetrix Configuration dialogue. Under "Preferences", click on "Positioning".
The first box gives you the option to use theme specific positioning. If you want all themes you use to dock in the same place, leave this unchecked.
The second checkbox should be checked ONLY if you don't want windows to cover your Sysmetrix when maximized.
The H,V offset spinners which are immediately below the second checkbox allow you to move and position your Sysmetrix skin in realtime and fine tune the positioning.
The Screen-edge Snap To box lets you set a tolerance for how close the object gets to the Screen-edge before defaulting to a docked position.
The Movable and Locked position radio check boxes are self explanatory.
Also, Don't overlook the Window Position combo list box in the next section. This sets the Z-order for your Sysmetrix skin. On Bottom means nothing but the desktop will ever be under the Sysmetrix, On Top is similar to Always On Top, and Normal means it acts like any other window and will vary position relative to the desktop.
P.S. Don't forget to save your settings when you're through.
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