When you load your custom table in Database Configuration and go to the Relationships tab, do you see a relationship with a Name of WORKORDER? The Child Object field for that relationship should also be set to WORKORDER. On your custom table, I assume there are WONUM and SITEID attributes, so the Where Clause should be wonum = :wonum and siteid = :siteid, where Maximo will replace :wonum and :siteid with those bits of data from the current record in your custom table.
In your expression, your reference to WORKORDER.WORKTYPE is unbound -- it is missing the leading colon : that tells Maximo to use data from the current record. Corrected, that condition will be :WORKORDER.WORKTYPE <> 'CM'.
I hope that helps.
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Blessings,
Jason Uppenborn
Cohesive
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