Feature request for creating Live CD

I am running into a roadblock for creating a Live CD (or read-only USB
drive) version of Firefox where no installation to the hard drive is
required.  It seems that where profiles.ini is read from is hard coded
to be read from the registery.  While the "-P" flag allows selecting
from different profiles defined in the profiles.ini, it does not allow
for selecting an alternative location for the profiles.ini file
itself.  I would like a way on the command line to specify an
alternative source for the registery settings for firefox and to be
able to set the variables relative to the directory that firefox.exe
is running from.  Such that I could run "D:\firefox.exe -R regfile"
where regfile contains:

"Install DIrectory"="%CURRENT%\"
"PathToExe"="%CURRENT%\firefox.exe"
"Program Folder Path"="%CURRENT%\profiles\"
"Components"="%CURRENT%\Components"
"Plugins"="%CURRENT%\Plugins"

Hence, profiles.ini would be read from D:\profiles\profiles.ini given
that the CD is D: but also continue to work even if the CD drive is
assigned a different drive letter.

As far as I can tell, I am able to address the other issues of running
from a read-only media by a revised theme/configuration which strips
out the features of Firefox which would fail in such an enviroment
(disk caching, changing preferences, etc.).