Hi Imon,
I am having the same problem with a child theme. Whether I create the child theme by hand or use the Orbisius child theme creator, the website front page just shows a white screen.
MAMP Server
WP 4.0
Hathor 1.5
Tested the style.css file by plugging in several different parent themes, and they all worked. Everything but Hathor.
Thank you for the amazing theme and all the support!