TFS 1.X+ Exeta res not working

[Rodo]

I'm using the TFS 1.3 downgraded version to 8.60 and the unmodified challenge.lua file, but it just doesn't work, the spell is executed and no errors are shown in the console:

local combat = Combat()
combat:setParameter(COMBAT_PARAM_EFFECT, CONST_ME_MAGIC_BLUE)
combat:setArea(createCombatArea(AREA_SQUARE1X1))

function onTargetCreature(creature, target)
    return doChallengeCreature(creature, target)
end

combat:setCallback(CALLBACK_PARAM_TARGETCREATURE, "onTargetCreature")

function onCastSpell(creature, variant)
    return combat:execute(creature, variant)
end