Yabdab Form Snap Calendar module - toggle buttons invisible

This may be to do with RW7 upgrade but a customer has just pointed out that there are no calendar control buttons: http://www.typarke.co.uk/contact-us/. They are there, just invisible. Yabdab are away until 27th June. Any ideas?

Problem solved. Despite being on holiday, Mike at Yabdab came back with a stack update that fixed the issue. Great support. Thanks guys!