The roulette "Next server hash" appears to be working fine for me, however the explanation may be a little unclear. The Roulette "SHA256(Next Server Seed)" should be equal to the hash of the next server seed that appears in the "Server Seed" box. Basically keep a copy of the hash you are given, compare it to the SHA256 hash of the next value to appear in the "Server Seed" box after playing a game.
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