The "Start conversion" tab on the left should not automatically start converting!!
In the process of setting up the conversion I click the tab button, thinking there were more settings there and/or just to see what's what.
To my surprise the conversion started immediatly filling up the wrong destination map.
I ended up spending half an hour cleaning up my HDD (because my map structure in my email programs resembles map structure on the HDD).
As such, there should be a 'start' button on the "Start conversion" page itself!
Second suggestion: the ability to extract attachments from emails into there own output directory.