Go to your steam workshop folder, find CE folder and find Races_Mechanoid_Light. Then open it with notepad and delete (<Operation Class="PatchOperationReplace">
<xpath>Defs/PawnKindDef[defName="Mech_Militor"]/combatPower</xpath>
<value>
<combatPower>60</combatPower>
</value>
</Operation>)
After that save the file and launch the game. Should be working just fine (probably). Atleast you won't be getting this annoying message anymore.