Musejazz style

I want my piano grand staff score to appear in the musejazz style, I can easily select that choice for a single staff, but I can't set it up for the grand staff with which I'm working. When I go to the "Format" tab and proceed to "Style" I can see the "musejazz" option. When I click it on, my score changes to the way I want it. But the webpage is too tall - I can't see the entire "Okay" in the blue box at the bottom. When I pull the top of the page further up with my cursor, I can see the "Okay" box, but when I release my curser to click on that box, the page drops before I can get down there to authorize the change. How can I fix this problem?