For those having issues with engine shrouds showing up all the time: Edit the config file \Klockheed_Martian_CoolRockets\stock.cfg. The issue seems to be fixed by deleting all passages looking like this MODEL { model = NASAmission/Parts/Size2LFB/Size2LFB scale = 1.0, 1.0, 1.0 } except for the cluster engine (else it will be broken in VAB).