I've not noticed this with other installs (but I might have overlooked it); not
sure if it's specific to the machine or generic.

I did a graphical NFS install (using an exploded NFS tree, not loopback ISO
mounts).  When I got to package selection, I selected several major groups, and
then hit details on a couple to add additional packages.

On Engineering, I hit details and tried to select all seven packages in the
category.  I put checks in all seven boxes, then clicked okay.  The details
option then showed 5 / 7 selected, so I went back into details and discovered
that blas and lapack had magically become deselected.  I selected them again,
hit okay, and saw the same thing (magically deselected again).  I repeated this
several times to make sure it wasn't pilot error...

I was eventually able to select blas and lapack only by deselecting all packages
in Engineering, hitting okay, then going into details, manually selecting blas
and lapack, hitting okay, hitting details, adding the other 5 engineering
packages, and hitting okay.

I also saw something similar with Mail Server.  Selecting postfix was similarly
impossible, and I was only able to select it by deselecting everything else,
selecting it, hitting okay, then reselecting everything else.