Conflict with Grid-fx plugin

Website : http://portesnadeau.doordoctor.com
(I've granted you access)

Since update 1.5 of Appointment+... it generate false <p></p> in source code so CSS does not load properly.

Sreenshots:
When Appointment+ IS NOT activated :
http://prntscr.com/4x86fy
http://prntscr.com/4x8641

When Appointment+ IS activated :
http://prntscr.com/4x86u8
http://prntscr.com/4x876a

NOTE : This problem occurs only when I use shortcodes in pages [gridfx columns="4"]

But if I of I do it directly in the php like this echo do_shortcode('[gridfx columns="4"]') ; ... Everything is ok!

Grid-fx plugin :
http://codecanyon.net/item/grid-fx-ultimate-grid-plugin-for-wordpress/5615317

Thank you.