Hello,

Why only bypassing TRUE logical values?

=LOOKUP(MAXNUM,B7:M7/(ISNUMBER(B7:M7)*NOT(ISBLANK(B7:M7))))

Set MAXNUM to 1e307 or something you can live with. If you really need
0 instead of blank cells (which I would prefer because a result COULD
be 0) to represent non-filled cells, substitute NOT(ISBLANK(B7:M7)) by
(B7:M7<0).

Regards,
Bernd