Exclamation C-Rom ver 7.1 Problems

I installed the firmware version 7.1 on my GT-N7000. What problems I've found using: 1. sometimes it temporarily hang the phone, doesn't help anything but restart button on/off. 2. Music from an sd memory card is visible not all, only some folders, and each time you restart a different number of folders. 3. Sometimes there is an inscription "the application has failed". Compared to version 6.6 phone has become slower to work and sometimes frozen. I'm sorry, but it's annoying. I'm going back to version 6.6