The Messages Beta on Lion was great and worked perfectly but ever since switching to Mountain Lion and using the *official* release, I have had nothing but problems. Two issues: 1) Messages.app keeps asking me for my iCloud password. I enter it and nothing happens. 2) It won't stay in sync with my iPhone and iPad (yes, I'm using my email address for the iMessages on all devices). It eventually syncs after a while or when I enter my password when it prompts (syncs this way very rarely). Anyone having the same issue(s)? I've Googled and tried different things people have posted on the Apple Support site but nothing has worked (from what I've seen).