Edit: That first link: https://azdude.wincustomize.com/skins.aspx does not work, and I also got the dreaded HTTP Error 404 message. But I'm still able to download any of your skins from the galleries.

Try this:

If you go to the http:// site and the page doesn't load, click somewhere in the page and type in thisisunsafe and hit enter. It may go then....

Most Browsers started marking HTTP websites as unsecure in 2018. Now, most are enforcing it.

It could be as simple as the SSL/TLS certificate for that server being expired, and just needs to be renewed.

I always use the search box on WC and enter my id, it will bring up all your work, copy and paste. Hope it helps.

That will be the cause....the solution may be an issue due to all the site interlinking.

Entertainingly....the Admin site is called '2007' ....so it's older than my underpants....

That's correct...the knickers part.   

Unfortunately, the site is too antediluvian to support https, so use Brave or Firefox, or edit out the 's' by hand.