Just trying out the Dataflow feature and sadly anything other than US date format does not appear to work. I am using a DimDate table which has dates in UK format. Created a Dataflow, all date field that were in UK format came in as US Format - as far as I can see there is no where to set the date format to UK. So i then connected to the Dataflow from the Desktop and all the date columns error because the service thinks they are invalid dates. There is life outside of the US :-) If this is a bug please fix it quicker than you did when PBI first came out and the same US/UK format issue took nearly a year to fix.