Help making a port for a (somewhat) restricted program

[Vitaly Magerya]

I'm creating a port for Petite Chez Scheme [1], which is a free interpreter
for commercial Chez Scheme, and has some licensing restrictions.

>From what I understood in the license [2], user must accept it before
installing.
The text of the license is also distributed in the tarball, so it
seems appropriate
to simply display the license file on post-extract.

Is there a common way to display such a file before installing?
I'm currently using ${PAGER} for that [3], but it's unlike any other
port we have.

There's also a problem with packages: you can't create one unless
there's a way to show the license on pkg_add. I believe that pkg-install script
can be used here, but I don't think that putting the whole license inside
hat script is a good idea.
Currently I've forbidden making packages; any thoughts on the right way
to do that?

And the last issue: depending on a command line switch the port
requires fetching two different files. The way I've set it up is to set
a parameter depending on the switch, and then use it in DISTNAME.
In short, that makes portlint go crazy. Help on this is also appreciated.

[1] http://scheme.com/petitechezscheme.html
[2] http://scheme.com/download/petite-lic.html
[3] http://tx97/pub/patches/petite-chez.shar