Switch input/KB layout on a Dell Inspiron, anybody PLEASE!

[Thomas Blasejewicz]

Good evening
I REALLY need help, but so far I could not find any answer on
any of several mailing lists, forums, Dell support ...
(I DID ask here before and therefore are likely to make myself very
unpopular)

Problem:
* I am trying to install Linux on a Dell Inspiron 1545, 4 GB RAM, 320 GB
HDD, perfect working order.
* NEED to be able to switch between Japanese alphanumeric + character
input methods.
* NEED to be able to switch between Japanese + German KB layout.

* By now, I know how to set up input method / keyboard layout.
* It "did" work, not good but somehow, using UBUNTU 12.04, 64-bit

HOWEVER ...
when using ANY other distro(*) the keyboard layout switcher is disabled
when I touch
the input selector just ONCE.
(* Ubuntu, Xubuntu, Kubuntu, Debian, Fedora, openSUSE ...you name it)
Changing the physical KB model during installation or later has NO effect.
Changing ANY setting for the KB layout brings it "back to life",
only to disappear again when I switch the input method.
It does not matter, whether I use keys or the mouse to change KB layout
/ input method.

Being able to TYPE in different languages using two different KB layouts is
essential for me working as a translator.

Has anybody ANY idea how to fix this strange behavior?

(this switching works on an antique PC running lubuntu and
a Mouse computer laptop (with ten-keys) running xubuntu ...)

Thank you.
Thomas