Just to set the record straight, I'm no serious unix compile whiz, just a long-time user that can compile the avg stuff.
First things first, do you make those links in /usr/bin or /usr/lib? (your post on macnn said /usr/bin, they need to be in /usr lib)
Also, one would think configure would do this for you, but go ahead and create the /usr/local/lib/trn directory
sudo mkdir /usr/local/lib/trn
It may be that /usr/local/lib doesn't even exist on standard installs, so you may have to mkdir that first.
Now then, the termcap link is supposed to set things up so that the curses library is used as the termcap lib. So you should be able to answer yes to that question.
Here is link for porting tips that generally speaking I have followed, so my system may be doing other things for me now that I didn't realize I needed for trn (since I had compiled other things like elm and mutt)
http://gnu-darwin.sourceforge.net/porting.html
Other than than, yes the trn script asks a gazoogle of questions.... mostly I think I went with defaults... and you won't have ispell installed so skip that (you can get it via Fink).
Hope this helps you make some progress,
Mike