I use maintenance mode fairly regularly but with m-turbo the cached version seems to show up regardless of whether magento is in maintenance mode is active or not, rendering maintenance mode useless. Can you tell me how to either temporarily disable m-turbo or to get it to play nice with maintenance mode.

Yes, M-Turbo ignores maintenance mode. You can comment the directives in the .htaccess file. This is the fastest way to deactive M-Turbo withou deleting the cached pages.

The .htaccess file can look this:

....

############################################
## M-Turbo Accelleration (www.artio.net)

..... some directives to comment ...

## End M-Turbo

.....