We are using this interface to get a line from measure A to B.
If the return polyline is on the first polyline we get zero from esriLocationError
If the line span to the second polyline we get the correct result but the esriLocationError is 7 or 8.
For example we have one line with measure 0 -9 and a second line with measure 9-21.
If we ask for locate on 5-7 we get return zero. If we ask for 8-15 we get the correct line but status different from zero.