I've just downloaded the sample code, but when I try to open the files, Excel 2013 shows this message:
We found a problem with some content in '***.xlsm'. Do you want us to try to recover as much as we can?
If you trust the source of this workbook, click yes.
When I click yes, the VBA file is removed.
When I click "Yes", then the next message is
The workbook cannot be opened or repaired by Microsoft Excel because it is corrupt.
I've added the folder containing the download files to the Trusted Locations, completely disabled trusted view and also tried to run Excel 2013 as Administrator - nothing helps.