This looks familiar!
If you're going to make me keep the page open, then the transaction should be instant. Any longer than that and the risk of accidentally closing the page is too high. Every other site that does this is 0 confirmation. Perhaps you should keep a wallet for each account, so fewer accidents occur.
When does the round creator get the fees?
0 Confirmations a bit risky. They display them after 0 Confirmations and then credit the accounts after 1 usually.