Confusion about MacOS downloads

[pwhirley]

I am trying to install PXPlus on my MacOS for the first time. I'm running MacOS Tahoe 26.5.  On the downloads page I find the row that says "MacOS - M1 MacOS Sequoia v15.4 64 Bit.".  It shows a date of 2026-May-20 and size of 33MB.  Sequoia doesn't match Tahoe, but I figured it might work.  The file download button says "pxp2300-0000-MM1-64.taz".
The actual download is not a TAZ but a GZ, which shouldn't make any difference.  It is, apparently, automatically extracting when it lands on my system.
Once there, I attempt to run the executable and it fails every time:
zsh: exec format error:"
Is this a problem with my OS version or am I doing something wrong?  If it is an OS version problem, when with a MacOS build be available for Tahoe?

Thanks - Phil