My guess is it's one of two things. The Dev hasn't tested with a Boxchip (?) based device and excludes it (most likely) OR the dev did test it and it doesn't work. Ways around it? If the tablet is rooted it may be possible to change its id, though development like this is not assured with off brand stuff like the flytouch. Maybe try contacting the dev for a test apk. For the record, getting the apk by other means is not a discussion for this forum. Good luck!
Since this is specifically tablet related, I'm moving it to the general tablet section.