Problem with using basic paraxial optics toolkit

I have already tried a lot of things in order to run a function, especially the LaguerreGaussianE function but still it won't work. Maybe I'm still not familiar with the concept of Laguerre-Gaussian beams or I just don't really know how to use functions. Anyway, you can download the whole package of the basic paraxial optics toolkit . Every time I run the LaguerreGaussianE.m file, I get an error message like this:

 Error: File: LaguerreGaussianE.m
 Line: 191 Column: 1
 All functions in a script must be
 closed with an 'end'.

Any help or advice would do.

Thanks,