The lookuplast( function is supposed to skip the current record. In Panorama 6, as a formula fill was being done, the current record would advance from record to record, so that lookuplast( would skip whatever record was currently being calculated. In Panorama X, it is checking the record that was current before the formulafill started, the current record is not advancing. Pete Schuder submitted a database (IRASampleX.pandb) where this causes his procedure (FillStocks) to not do what he expected.
#703, which is probably related (grabdata( function doesn't work in FormulaFill to access current database).