In your BCS Data Log page, there's a link to save the log as a text file. Use this utility to view saved data logs.
http://www.embeddedcontrolconcepts.com/utils.html
The data log flash utility embedded in the BCS-460 and this viewer are based on the open source project Open Flash Charts. So feel free to test it out for yourself.
http://teethgrinder.co.uk/open-flash-chart