The enabler hack seems to have worked -- no error message, and I now have an empty folder "/mnt/us/acxe/"

is this folder necessary?
But adding gtranslator.acx at {$KindleDrive/}"system/acw/" does nothing. I should see an
extra option when tapping on a word, correct? I see no changes... It hasn't overwritten the default translation acx (I didn't think it would, but checked anyway) since it still shows default languages, not your list.
I haven't tried adding it to "/opt/amazon/acw/" but I will grab kterm extension and cp it over.