I wrote this little code to look for a bouble-bytes char that would use $chr(160) as it's first byte.
//var %i 0 | while (%i < 256) { bset &t 1 160 %i | echo $bvar(&t,1-).text | inc %i }

All those "combinations" seem not to match double-bytes chars. Most of them show a "middle dot" character followed by some other char. (tested with MS Gothic, jap script).

Reversing the order of bytes (bset &t 1 %i 160) indeed shows much more *real* double-bytes chars!