Yep there are possiblilities of your phone bricking using XS++ but you can just flash it again.
You are correct about the FS:
W810_R4ED001_FS_AMERICA_1_RED50
The MAIN you will need
You will need the same R4ED001 and generic. You can update to CID52 and use the 52 instead of 50.
And you will need the custom files for the languages.