Hi
as a workaround
for unmatched backs:
(bu_1_backa*bu_1_backp)+(bu_2_backa*bu_2_backp)+(bu_3_backa*bu_3_backp)....etc.
or
(s_1_bu_1_backa*s_1_bu_1_backp)+(s_1_bu_2_backa*s_1_bu_2_backp)+(s_1_bu_3_backa*s_1_bu_3_backp)....etc.
make it as long as you need to cover your max number of unmatched bets
for the lays it's the same, just replace backa and backp with laya and layp