Portable Truecrypt/AxCrypt

The Axantium website seems to be down at the moment, although there is aa AxCrypt2Go version on sourceforge, which sounds like you could maybe work with.

TC is already inherently portable, apart from the little fact that it needs administrator rights on the PC to run, though many of us already use it routinely on our portable drives. The simplest of searches here on the site will turn up many many hits, including apps such as geek.menu that fully integrates with auto-mounting TC volumes when appropriate, and runs an app set from them seamlessly.

As for the Free Download Manager, as was stated in your previous thread, a couple of people who have looked at it in the past found that the app itself was very badly behaved and interfered with the standard firefox install on the host PC. I would suggest that if you really want work done on this, that you might talk to the authors of the app to see if they can improve on it's behaviour in a portable environment. Remember that the people here on PA.com basically give their spare time to these projects, so unless one of them happens to need the app personally, then the ones that are highly problematic are unlikely to ever get attention.