comparing additional columns

Hello,

We do not want any CDR. But we want additional protection by comparing an additional column during replication. So we want replicat to compare the key columns and additionally one other column. However that comparison is not an equality comparison i.e. it is not source col = target col. Instead it is source col >= target col. I guess COMPARECOLS with Keysincluding is the only way but how do we check for >= ?

Secondly, is there a way to instruct GG to compare the After image from the source with the target value? It seems to be comparing the Before image always.