My constraint is ignored, even if it covers some paths:
"WARNING:ConstraintSystem:80 Constraint %s: This constraint will be ignored because one or more of its specified associations could not be found."
This problem is usually caused by two reasons. One reason is that this constraint is overriden by other constraints with higher priority. For example, the FROM THRU TO has higher priority than the FROM TO constraint. The other reason is that the timing group referenced in this constraints does not include any elements.