Multiline prompts and vi editing mode

[Michael Grubb <zsh@xxxxxxxxxxxxx>]

I'm a brand new user of zsh, I'm thinking of converting from ksh which I'v used for many years now.
I also have used vi editing mode for so long that it is simply second nature and I don't really care to try
and form a new habit.  I've also been tinkering with some of the features from oh-my-zsh, specifically some
of the themes that feature multiline prompts.  I have noticed however that when hitting Esc to go into command
mode that I'm loosing the last line of output from the previous command.  Is this a limitation with multiple line prompts, a setting I need to change, or a bug?  Also in ksh I can use Esc-\ to invoke command completion, though that doesn't seem to work with zsh, any tips on getting that configured would also be very much appreciated.

Thanks in advance,
Michael Grubb