An archive of repair files. Shared as “STAR-X C98 COMBO_V2.00_2017-2-15 By 0iue .rar” — a .rar file, 3.04 MB.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @led_software. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
7-ZipWinRARThe Unarchiver (macOS)