I had the same problem...
Google has changed CORS Policy (due to security reasons) and you cannot open files using other programs, anymore.
I found a solution for anyone who is interested in:
The link we were using in order to open a csv file was something like this:
In order to bypass cors policy and open your csv file, the link should be in this format:
* You can find the sheet key by opening your sheet file in google drive
** SHEET_NAME, not your file's name