I think that you are the only person in the entire world who uses a mouse to control MP . However...Wow!!!....can it be that I'm the only one experiencing this problem?
Having now tried this on my production system (MP 1.24F on Windows 7), I too cannot get the top bar to appear. By "top bar", I mean the horizontal bar that contains the traditional VCR player controls (play, pause, stop, forward, rewind, record, possibly a few others). There is a skin file called "TopBar.xml" that contains the definitions for these controls.
I tested "DefaultWideHD", with both my usual "Centarea HID" active for the remote control, and with that disabled and a standard MCE remote enabled instead (I also exited from the "Centarea HID" AutoHotKey script, just in case that was interfering with the mouse signals). I also enabled the "Show enhanced mouse controls" setting (in "GUI Controls" in "MP Config"). None of these different combinations could persuade the top bar to appear.
The only thing that did appear was the info OSD, which appeared when I moved the mouse pointer towards the bottom edge of the screen (when playing live TV).
I use the standard EVR (not Madvr), so I think that there is definitely a problem...
-- from CyberSimian in the UK