The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From Box Office Tickets:
NOTICE: THIS APPLICATION IS ONLY FOR BOXOFFICETICKETS.COM EVENT MANAGERS AND IS DEVELOPED TO WORK WITH THE LINEA-PRO PORTABLE INTEGRATED BARCODE SCANNER COMPATIBLE WITH IPOD TOUCH.RoBOT StopLight provides wireless, realtime ticket validation.RoBOT StopLight makes it easy to use wireless ticket scanners to speed and simplify admission control at multiple entry points throughout a venue.This application requires a current management account with the boxofficetickets.com network. Please consult a boxofficetickets.com customer service representative for assistance or questions, 800-494-8497.