not sure, but what i do is set the application to open in a window instead of full screen, and simply move the widnow where i want it. Not as elegant as what you're wanting to do, but it gets the job done.
If you look in your wine config file, you'll see an option that is commented out by default. I think it says:
i run my resolution at 1280x1024, so if you set that desktop option to something lower that your resolution, and uncomment it, all apps will open in a window of that size. If your mouse gets locked into the window, just minimize all windows using whatever keyboard command you set up, then select your wine app from the taskbar, and move the cursor AROUND the window up to the title bar and drag it to where you want.
My config file reads:
removing the ; uncomments the line and makes it active.
-myk