I know the trick to install stand alone applications in portable apps menu
Say you want to install Universal extractor
Download universal extractor.zip from a any mirror.
Create a Directory with any name (eg: universal extractor) in the PortableApps folder.
Now extract the content of this zip file in to into that folder.
In portable apps menu click options and Refresh apps icons.
This can be done with any application on a condition that the directory in which the app is installed or extracted does not have 2 *.exe files. Otherwise both these *.exe files will be viewed in Portable Apps menu.