I have an older but I thought not totally obsolete notepad running XP
1) downloaded mscore-0.9.3.exe from sourceforge, installed and ran it
2) displayed ok except for the big window in which I believe the score is supposed to be, which was nondescript grey with a black box in the lower left corner. Using Preferences, I have been able to convert this to other colors and/or wallpaper (after informing it where the "wallpaper" subfolder was). The only changes that I could see were to the "background" setting. Still can't see any score, notes, measures, staves (staffs?).
3) opened a score (Adeste) - score did not display. But when I clicked the play button it played once. I've since closed and reopened the program and tried adeste and other demos, but none play now.
4) in pallette display the pulldowns for clef, etc each show 12 identical staves without any clefs, signatures, etc.
5) I rechecked your system requirements and found that you say display 1024 by <786>. My display is 1280 by <768> which I hope means that yours is the typo.