crossing waveguide 3D FDTD don't have a result.

[LinHanswjtu]

when I change the SIZE of the corssing waveguide into a bigger one, the program has worked for a long time but don't get a result.
In Example One, I change the length of crossing waveguide to 6 um.Both of the "FDTD_crossing.lsf" and the "crossing_opt_3D.py" has changed. The program has running for several hours,but no FOM is calculated.
In example Two,I change the length of crossing waveguide to 6 um. I only change the "crossing_opt_3D.py" and don't change the "FDTD_crossing.lsf". In another word, the location of input waveguide, monitor and the size of FDTD do not change. (they are for the example of 4um- crossing waveguide). However, it has a result. it can calculate the FOM.
so I don't know where it is worng. could you give me some suggestions.
this is original result of example one.

example two do not have a original result.
example1.zip
example2.zip