Hey guys, I may have something related to this. I just downloaded the beta patch for P3D 4.5 too and noticed that only "Download" in "Download Link" changed color to indicate it was visited.
I hovered over "Link" and it points to a different link.
I downloaded them both and compared - the "Download" download was signed April 6, 2019 and is 84,071,848 bytes in size, and the "Link" download was signed March 15, 2019 and is 83,790,752 bytes in size.
Until that gets sorted, I bet a lot of folks might get an old download. The "Download" part of the link is probably the correct one but I’ll wait to install until HiFi lets us know.