Actually, with this Flash plugin I can get Cityville (a nice test tbh) to run. It crashes while loading the city and buildings, after the main loading screen. With older Flash it just hangs at 50% of the loader.

Install it with these three commands:
1) wget <a valid URL>
2) mv /usr/lib/browser/plugins/libflashplayer.so /usr/lib/browser/plugins/libflashplayer.so.bak
3) mv libflashplayer.so /usr/lib/browser/plugins/libflashplayer.so