Fundingpress installation and activation on wordpress (php error, website host say they can’t solve)

I bought fundingpress theme less than a week ago but I am now regretting it. First I tried to install it in wordpress following the instructions and it said: “Are you sure you want to do this. Try again.” I then installed it using filezilla ftp and it was installed. BUT, after clicking activate everything goes blank. After clicking preview everything goes blank. Now I can’t even log on to my wordpress site. Everything goes blank. I contacted my webhost, bluehost and they said it’s a php error and they can’t solve it. Only the theme owner can. Please help. I’m now stuck in mad, shitting, pooing and peeing on myself.  Pliz, pliz help.