Use these files:

1. C702_R3DA029_MAIN_GENERIC_NG_RED52
2. C702_R3DA029_FS_AMERICA_RED52
3. K850i_1201-0089_R11A_GENERIC_AMERICA (no problem with K850 custpack, because C702 use same).

After flashing with A2uploader -> update via SEUS to lastest version R3EK002.