Yes, 64-bit KSP, 32-bit won't run without dying through lack of mem. (Yes, am running texture reducer and have done all the usual memory reduction settings). Module Manager 2.5.9 installed by CKAN. Have tried the ConfigCache delete trick, saw that in another post. Have also tried downloading from this thread and installing that, still no joy. I believe that CKAN installs the Realism Overhaul config as part of, I certainly see engines requiring Kerosene etc.... Edit 2: Right, have just done a full, clean install of KSP and RF (& Module Manager) Only, with Stock configs, and it is 64 bit that is the problem, works fine in 32 bit. Real shame as it means I can't us this mod as my 32 bit won't run with everything else I want to support!