Symptom
Operations are left unscheduled when scheduling backwards with constraint set as Increment from Start and Decrement from End.
Cause
Default high and low values are not defined, therefore a maximum and minimum of 0 is used. The final check on the constraint is violated between 'time zero' and the scheduling horizon start because it exceeds the maximum allowed value.
Solution
Add two fields to the 'Secondary Constraints' table in the 'Preactor.prtdf' file defined as follows:
Max. Value,0,INTEGER,
GRAPH HIGH VALUE
DIALOG ONLY:
Min. Value,0,INTEGER,
GRAPH LOW VALUE
DIALOG ONLY: