Subscription form shortcodes not working?

I tried to use one of your subscription form shortcodes (ref: https://tribulant.com/docs/wordpress-mailing-list-plugin/37) but whenever a user clicks on one of the lists it clears the email address, thus making it impossible to subscribe. For reference, this is what I was using:

[newsletters_subscribe lists="1,2,3,4,5,7,8,9,10" list="checkboxes"]

Have you dropped support for the shortcodes or is this just a bug or am I just missing something?