When working on the Release Preview version of an account, images may come up broken or custom styles may not be applied to the web store. The reason for this is that the Production account uses URL Components for these images/stylesheets, which will only work when there is a domain. It will not work if the base domain of the web store is shopping.na1.beta.netsuite.com.
As of version 2013.1, the Release Preview web store CName is shopping.na1.beta.netsuite.com and the IP address which can be used for the A RECORD redirect is 184.108.40.206.To resolve this problem, use a domain for the beta version, utilizing the CName or A RECORD to redirect the IP address. An alternate solution is to disable the 'Descriptive URL' feature in the Release Preview version. This can be found under Setup > Company> Enable Features > Web Presence tab.