We completed a few Google migrations last week and found that there are still a few problems with the Mailbox Migration tool.
1. The only way I got the a contact migration to work was after selecting "authorize google" with a calendar import. Also the Mailbox Migration tool gets "locked up" for the mailbox after doing a contact only migration. I have to restart SmarterMail in order to use the Mailbox Migration tool again for the mailbox.
2. An Email only migration also "locks up" the Mailbox Migration tool for the mailbox. SmarterMail needs to be restarted in order to use the tool again for the mailbox.
3. A few mailboxes would not migrate messages with the Mailbox Migration tool. Re-running the tool sometimes worked but most of the time the fix was un-selecting the problem folder in Gmail by un-checking "Show in IMAP". I have a sample of the errors from our logs.
Webservices migrations had the same problems as the Mailbox Migration tool. We're using SmarterMail 13.4.5603.
The calendar migration works for us since our Gmail mailbox and SmarterMail mailbox name are the same.