WPML can be a little tricky to get a hold of.
It’s not the easiest of plugins to manage unfortunately.
In your Admin Dashboard go to WPML > Strings Translation and go to the bottom of the page.
There is a link. Click it.
You will then have the option to choose from a lot of strings to add to the Strings Translation dashboard.
You will need to select and add all the strings for the Integral pages and Widgets.
Once that is done you will have the option to translate them in WPML > Strings Translation.
Integral Pro comes with the language files and the WPML config file included.
So it does work with WPML, it just requires that you properly configure the plugin.
You can also browse the WPML support forums and documentation,