I have created snap start url like below. It does load the report harness however script and css does not seem to load.

http://myDevEnv/prweb/PRServletCustom?pyActivity=Data-Portal.DisplayRptBrowser&harnessName=pyReportBrowser&className=Data-Portal&readOnly=false&pzSkinName=pyEndUser  

I get the below errors when i try to open a report:

Error in the launched portal Uncaught TypeError: Cannot read property 'document' of undefined at line 3 Column 12977 file

Uncaught TypeError: Cannot read property 'document' of undefined