Theme causing problems

Hi

I have a site http://www.anger-management.co.il

Wpmudev dashboard is installed there

I cannot reach the theme author.

There are many problems in the site. which lead to pages displaying blank screen

also this link for instance doesnt work

http://www.anger-management.co.il/product/%D7%A7%D7%95%D7%A8%D7%A1-%D7%90%D7%95%D7%93%D7%99%D7%95/

When i change to 2015 theme all seems ok

Have tried disabling plugins. Didnt help.

Since I am unable to contact the theme author I kindly request you guys at WPMUDEV to assist as to what is causing this issue.

My client is really stresssed out.

Thanks