Bigfish - Font Book returns error

Hi Font support,
I am having trouble trying to install Bigfish font. I originally downloaded it from you, then I tried downloading it from the maker.
I am attempting to install via Font Book on a Mac Pro Running El Capitan 10.11.6
Font Book gives a fatal error and will not let me install.

Thanks for any light you can shed.
Could it be n ID conflict? I do have a lot of fonts installed and I am not using a font manager other than Font Book.