CSS error in BP-Fun Theme

I'm using the latest version of WPMU, BuddyPress and I am using the BP-Fun theme.

I'm getting the following error message in my server error log:
...../wp-content/themes/bp-fun/_inc/css/custom.css

There is no file named 'custom.css' in the theme. The nearest file name to this is 'custom-sample.css'.
Should I just rename this file to 'custom.css'?

Please help.