PHP 7 compatibility?

Yes, it’s compatible.
Here you can see more:
https://wp-types.com/toolset-requirements/

There are no errors in Types and PHP 7, I use it myself.

If you can report us this on our Dedicated Support Forum we would be glad to have a look:
https://wp-types.com/forums/forum/general-and-pre-sales-questions/

First, please register for free here:
https://wp-types.com/support/register/

I have registered an error in the paid support
https://wp-types.com/forums/topic/fatal-error-uncaught-error-call-to-undefined-function-simplexml/

Closing here then.