limited access to products prior to release date

I am a fairly new digital scrapbook designer setting up my store to sell digital kits retail. I pretty much have everything set up except for one major need as follows.

I have a creative team that creates layouts of my products so that I have usage examples available when the product goes live. I would like for them to access to products prior to going live so they can do those layouts for me. I CT for another designer as well. She gives us links to the product to download with a coupon that allows us to purchase the kit (free with the coupon), and use it for our layouts prior to the product going live. Then we upload web versions of our layouts to her via a private FB group that we use for general CT purposes and discussions. She can then pick and choose which layouts to use.

I would like to do this as well for my own creative team so that I don't have to store those files on an unsecured site for them to grab for use in the week prior to the product going live. I don't want those products accessible to customers because some of my CT members will download the files to do quality control on them. I don't want customers viewing and purchasing products before they've been gone over with a fine tooth comb and I know they are ready for sale.

What is the best way to go about doing this in simple english. I've worked with HTML but though I've done my own basic customization for the store, I'm still a newbie at php.

Any help will be appreciated. Thank you.

Twitch Restrict Categories 14c, one category for your group, the rest set for 'Everyone'.

Your team logs in and uses the products like products. When you're ready, either move the products to a unrestricted category or change the category restriction to 'Everyone'

The newest version is pending review in the forum plugins, it's also available on my site for free download.