I just checked 343 occurrences of "bool function" in 141 files. There are other missing returns, and several functions that should not be bool at all (no returns, not used as bool anywhere in code).

In addition to the already posted CritterSpawn.psc SpawnCritter() -- duplicate problem found in same file name in Dawnguard subfolder.

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12245-missing-return-false-in-carriagesystemscript/

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12248-missing-return-false-in-dunbluepalacearenascript/

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12246-missing-return-in-reanimateashpile/

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12247-missing-returns-in-critterbird/

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12249-missing-returns-in-byohhousebuildingscript/

http://afkmods.iguanadons.net/index.php?/tracdown/issue/12250-missing-return-in-byohhousescript/

Sorry, am just checking existence by hand -- not logic or correctness. Good luck with that.