Nice exposition, some things would need further / correct explanation also to klaatu (!), blame it on Porteus' not-so-well own documentation, now and here only this what is VERY important (though not Porteus specific): Porteus' XZM modules (as they are aufs / squashfs as in eg. Slax) do not "overwrite" anything on your machine, they interrupt your file system calls and make them believe that there are things that are not really there, so deactivating a module or restarting gives you an unchanged file system again, and if two programs conflict in shared resource file versions, you need not uninstall something, you just activate / deactivate modules - those modules may just be different versions of one library file, i.e. you can make a single file or a directory a module, and always your "initial" will not be corrupted by workarounds