Greatly optimized the script by recalculating shadow visibility only when needed, instead of every frame.
Misc. bugfixes.
I think it was irresponsible of me to not clarify this before, so I think I should do it now: I will no longer be actively maintaining or updating this resource. The latest release of the resource will be left up for download, but will not be updated by me. The download links for all older versions of this resource will be deactivated. Feel free to add-on or extend this resource as you please, but do not expect any updates/support from my end.
I apologize for any inconvenience caused by my extended period of inactivity.