Checking Totals in an explore raise an error when POP measure is being used in the explore

Hi

I was trying to implement the new POP feature and it works nice ly when

1 - you use a date dimension, if you dont youll get many rows in the result and not one as expected

2 - you dont check Totals in the explore,if you do check the Totals checkbox then youll get an error

please see attached pic showing the error and the query