Excel formatting formula help

This requires 3 dummy columns but should work a lot faster than the array solution I gave earlier.
In your example, in U2 copied down

Formula:

=IF(COUNTIF($U$1:U1,A2)>0,"", A2)

In V2 copied down

Formula:

=IF(LEN(U2)>1,IF(ISERROR(FIND("-",U2)),COUNTIF($U$2:$U$200, U2&"-*")+1, COUNTIF($U$2:$U$200, MID(U2,1, FIND("-",U2))&"*")+1),"")

In W2 copied down

Formula:

=IF(ISNUMBER(V2),IF(V2=1, "", MID(U2,1, FIND("-",U2&"-")-1)&TEXT(V2-1,"-00")),"")

Then the conditional formatting rule is

Formula:

=ISNUMBER(MATCH(A2,$W:$W,0))

See attachment