Ok Phil I understand i was very lucky. Thank you!!!
I was asking for an advice on where to find some files about BGR3 that are not anymore avaiable here in TWC. In particulat the one file that was needed together with BGR3 installation by SS6.1 mentioned at the end of the OP of this thread:
https://www.twcenter.net/forums/showthread.php?106060-BGR-V-20150324-Byg-s-Grim-Reality-(Supply-amp-Command-Series)-Guides-Updates-amp-Optional-Extras
"Data.zip: Important Update for BGRIII users with SS6.1 installer
If you installed BGRIII using the Stainless Steel 6.1 installer you NEED this fix. It is at the bottom of this post, called "data.zip".
Simply unzip it and place the resulting data folder here:C:\Program Files\
SEGA\Medieval II Total War\mods\Stainless_Steel_6\ , then
start a new campaign."