On my MacBook Pro i had ZD 1.04 for quite some time, and a couple of days ago i downloaded the new version 2.0.

I deleted the old version from the Application folder and "installed" the new one; the account setup went normally, i started ZD and it froze at "Loading..."

deleting the last installation didn't help; now the setup is skipped and the "Loading..." screen stays forever.

I believe somewhere there are files that have to be manually deleted... or...?