How to reproduce the bug:
The exported data contains only the string 'Date', but nothing else.
Ideally the exported data would contain a column for each of the selected rows, holding only the selected metric. For instance:
Date,Chrome,Firefox,Opera 2013-01-10,1234,1203,94 2013-01-09,1214,1003,64
Thanks for the report!
In 2c47fe3384924ca2402df084a95d34d1526dd2be: Fixes #3663, make sure multi row evolution export links use label array query parameter.