Our schedule uploader is a little picky, and we plan to completely revamp it in order to make it easier to use. Until that time, please make sure that your date format is in DD/MM/YYYY format.
In order to change this in Excel, follow these steps:
Select the date fields in Excel that you want to convert
Right click and select "Format Cells"
Make sure the "Number" tab at the top is selected
Then click on "Date"
Make sure you chose the 3rd option "14-03-2012" (see screenshot)
Save the file as CSV