It's great that there is the possibility to use the bundle Thunderbird with gnugpg and enigmail portable. But if you want to use gnupg with some other programs, e.g. psi, you need a keymanager, too. So you can use winpt, but you have to install.
I think it would be good to have standalone gnupg and standalone winpt, or a bundle with standalone gnupg and winpt.
There exists the bundle "GnuPG basics" with gnupg and winpt, but it's not portable: http://people.freenet.de/rose-indorf/
It's possible for you to do that - and, of course, are you interested?
Teuchtlurm (sorry for my bad english)