For the car-mode profile, as I already told fuel__2001,
ProfilesX can not be used to start specific actions. ProfilesX can
only change the profile settings (ringtone, vibra, ...)
But the whole benefit of ProfilesX is to define more than those
to builtin profiles.
So you could go the other way around.
Use ProfilesX to define a new profile "Car Mode".
(Just to have a special named profile)

Now your autoanswer script could listen on dbus for
the active profile (profiled emits a dbus-signal if the
user changes the active profile).
And if the current profile has this special name,
enable autoanswer or speaker mode ...

nicolai