Changing name of "Actual" and "Date" in 00Census column app stops working

[WangTara]

Changing column name of Actual provides warning: "Invalid Input: dataframe should have at least two columns named (ds & y)." The user can still select options under Select Filters but cannot Fit Forecasting Model.

Changing column name of Date to anything else, causes the shiny app to close. Warning in console says "Error in summarise_impl: Evaluation error: object 'Date' not found."

Changing other column names still ok!