To me, they make sense like:
I got it/ it was gotten
It shrunk/ it was shrunken
so I guess I'd use things like gotten and shrunken in passive sentences..
though i think "it can be got" is acceptable (not really sure. I rarely use
that construction anyway.) It seems like when got is used in an active
sentence it can usually be taken out or replaced by have (I've got some
coconuts) or it's past tense. I almost never hear people saying "I've
gotten," or gotten at all. Where I live, "boughten" is considered on the
level of childish constructions (funner! strangely, the theme for a fair [
my art class had to do pieces for it ] recently was "kinder, simpler,
funner." I wanted to boycott it on principle, but, you know, grades.)
For some reason I always have problems with drunk, drank, and drunken. I
drank, but I have drunk? I have drunken? I have no idea.
http://www.refrigeratedcake.comhttp://www.refrigeratedcake.com/other/theatre -- Vade Mecum (comic)