Slayer worked just fine started with default add-ons; and only slayer gamemodes, and then ending it resulted in the file being created.
ADDON Weapon_Sniper_Rifle
ADDON Weapon_SMG
ADDON Weapon_Shotgun
ADDON Weapon_Scythe
ADDON Weapon_Repeater
ADDON Weapon_P90_pack
ADDON Weapon_Mortar
ADDON Weapon_Molotov
ADDON Weapon_HEGrenade
ADDON Weapon_FlakCannon
ADDON Weapon_DoubleBarrelShotgun
ADDON Weapon_Crowbar
ADDON Weapon_Chainsaw
ADDON Weapon_Boombelt
ADDON Weapon_Assault_Rifle
ADDON Tool_Duplorcator
ADDON Tool_Fill_can
ADDON System_ReturnToBlockland
ADDON Gamemode_TrenchDigging
ADDON Gamemode_Slayer
ADDON Gamemode_Slayer_CTF
ADDON Gamemode_Slayer_OneManArmy
ADDON Gamemode_Slayer_Territory
ADDON Event_setPlayerTransform
ADDON Event_Variables
ADDON Event_AddItem
ADDON Brick_FloatCubes
ADDON Player_NoCombat
ADDON Event_ItemSaving
ADDON Item_Pill
ADDON Server_SavedScore
ADDON Script_HealthBar
ADDON Gamemode_TTDM
ADDON Weapon_Revolver
One of these add-ons is conflicting with it in some way.
And I'd really appreciate a horse damage fix soon; I can't leave my dedicated server otherwise.