every time I tried to unzip the file the computer keeps telling me that the source file is corrupt
Yeah it's a common problem It seems.
Here's a link to the FAQ. There's a section on how to unzip:
https://blendermarket.com/products/human-realistic-portrait-creation-with-blender/faq
Also here's a copy paste of some answers that has solved this problem for people:
"This did help! There was an answer by Spikey on one of the questions that set me right. Here is what I was doing wrong. They need to all be in the same folder. Make sure the naming convention is correct. My computer automatically gave (1) to the initial zip cause I had downloaded it a second time. When they are named correctly and in the same folder, just unzip the first one with 7-zip. I heard they all need to be unzipped together and interpreted that as I needed to select them all and unzip. When I just did the first one, it worked and I got all the files. Hope that helps anyone else."
"I finally got it working! Apparently I needed to download an earlier version of 7-zip for it to have the right extractor options. (Not just any windows version because there are a few.) Since I have a AMD x64 system I downloaded version 19.00 / 64-Bit x64 / Intel 64 or AMD 64. Hope this will help for anyone in the future having the same issues as me"
"Yikes, that's a bit of a mess. It looks like you've downloaded the same file multiple times. Once you get rid of the duplicates (as denoted by the (1) and (2), etc) they should order correctly if you sort by file name. I suspect the duplicates are from failed downloads that were restarted. You'll want to make sure all the files are completely downloaded for successful unzipping. NOTE: All zips should be 1 GB in size except for the last in the sequence."
