An error occurred while attempting to retrieve the KPI value from the list

Ever encountered this error while tying to play with KPI for first time ?
Well i had , listing the causes which might throw this error:

• Make sure the columns are all available in the default view, else try selecting "All Document" view first
• I read that creating KPI in different site collection might throw this error, but never tried myself

In case looking for complete explanation of KPI , check out webcast :

http://channel9.msdn.com/Screencasts/214755_Dashboards.wmv

Enjoy!!!!