Im assuming this is a big file so you may need to break it
up and then have it reassemble after downloading.
Here is one way that may work for you using 7zip (free)
How-to: Break up large files easily with 7-Zip | PCMech
Watch the video on how to do it.
Create a download page with your download and a link for 7zip for your
customers to download it (free)
and maybe put together a pdf or short vid how to extract the zipped file
for them to use/watch your video(s).
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