Hi Frank,
My last "log" isn't representative because I tried some manipulations to try understand. But, look this METAR generated by MAXX METAR.rwx from Noaweather plugin. "2016/11/23 16:00
LFBO 231600Z AUTO 12015KT 070V150 9999 BKN027 BKN072 OVC092 17/12 Q1002 BECMG 12020G32KT"
With it, I has only one layer of broken cumulus.
Other caracteristic symptom: before when I set RWC "automatic" or "always", I has noted one clouds pictures difference betwen the two settings. Now, with "automatic", I lost the clouds ! Sky clear ! Only are existing on "always", but no realists in relation with the METAR. If I desactivate RWC inside the add-on settings, no effects like RWC inoperative all time. I reinstaled it without results. However, SkyMax seems OK because it picture respond at the settings change.
Well, that's all for this moment. I will continue my tests for understand why I can't use the native MTO from XP !! Cheers.
Note: the RWC plugin include only four files: "64"; "eula"; "registration"; "pdf rwc" and the "uninstall" file inside "x-aviation"