You have to place it into /home/user/ (or anywhere except MyDocs), because MyDocs is a vfat partition, and it can't have Unix permission bits set the same way as the other filesystems can. Also, add a shebang line and make it executable:

• Add "#!/bin/sh" as the first line of the script
• Save the script in e.g. /home/user/wtc.sh
• chmod +x /home/user/wtc.sh
• Add to Billboard: {script:/home/user/wtc.sh}