CutInfo error in ngsxfem

Dear developer,

Sorry to bother you, I have successfully installed the ngsolve and ngsxfem and done some calculation with ngsolve. When I try the tutorials and the demos in the ngsxfem, the test cases with class CutInfo, the programme cracks with :
segmentation fault (core damped)

PS: Other functions and class works well in ngsxfem, I can create the levelset function and etc such the demos without any problem.