I found a bug in ObHack 006b. Occasionally, the "You found a secret area!" message pops up when I stand outside a secret door, which spoils a secret.
In more detail, with the seed "OB-Doom1-200906" (no quotes in the actual seed), using the game "Doom 1", the length "Full Game", the mode "Single player", and with the following adjustments: Level Size "Small", Monsters "Plenty", Puzzles "Heaps", Outdoors "More", Switches "Keys only", Steepness "Some", Health "Enough", Ammo "Enough", and Start weapon "Basic", in E1M3, the secret area leading to the secret level gives me the "Your found a secret area" message when I stand outside the secret door.
I hope to find time to fix this bug this week sometime and released ObHack 006c with this one bug fixed.