Судить будем
вместо
qbr = q.dataSourceTable(tablenum(LedgerJournalTrans)).findRange(fieldnum(LedgerJournalTrans, JournalNum));
if(!qbr)qbr = q.dataSourceTable(tablenum(LedgerJournalTrans)).addRange(fieldnum(LedgerJournalTrans, JournalNum));
юзайте
qbr = q.dataSourceTable(tablenum(LedgerJournalTrans)).findOrCreateRange(fieldnum(LedgerJournalTrans, JournalNum));
qbr.value(ljt.JournalNum);
заменить на
qbr.value(queryValue(ljt.JournalNum));