Abh Mod version 0.5.0 works with Cosmoteer 0.13.0_rc1 and probably the full release version 0.13.0, too. Only the few new changes won't apply. You only have to edit the compatibility line in mod.txt
CompatibleGameVersions = ["0.12.12"
"0.12.11"
"0.13.0"
"0.13.0_rc1"
"0.13.0_rc2"]
ModifiesMultiplayer = false