I've sent him a message regarding this topic, maybe he can help you out.
Thank you.
Hi there, i was linked here by Lutpin and asked if i could help. Your details are a bit vague. What kind of testing would you like? Will you provide the source or you just like us to check the demo site and find bugs?
Anyway, i did checked your dice demo site, and immediately found this bug. As you can see on the screenshots, i was able to 'dupe'/'repeat' my rolls using the same seed/nonce, and thus,it gives me the same result.
1st try
2nd try
3rd try
Uhm, this looks oddly similar to dicebitco.in