Just to be clear regarding point 1, you are not creating a point source with the input plane. We have a point source, you are injecting a Gaussian beam along the input plane.
As for your questions regarding the specifics of the 32-bit software, the 32-bit free evaluation is an older version of the OptiFDTD product that we make available for the community. Along with other members of the community we work to help you understanding the use of the product or aspects of design. That being said detailed technical support and work on any bug reports is only available for users of the paid 64-bit software with a valid maintenance license.