I don't undestand.

Xournal is, right now, available only for Chinook.
When you install it (on Diablo via the Maemo.ord Downloads section), it will enable two CHINOOK repositories (extras and extras-devel) for the depencies it needs.
AFAIK there is no easy way for me to disable both of them after the installation.

You should do it by hand by going to the Application Manager->Tools->Application Catalog... and disable both of them (by editing them) or removing them.

This is the only way to install Xournal on Diablo.
It will NEVER appear on Diablo's application list because it is NOT listed in the user's repositories.

If it does, you guys have somehow installed/enabled the Diablo's -devel repository.
And this is, sorry, not my fault.

Even if I put Chinook's version of Xournal in the Diablo's repository, the issue will arise anyway as the very same people will find an update and go for it.

A solution would be for me to pull out the -devel version.. we'll see.

So, when Xournal does not work on your Diablo: remove it, disable the Diablo's devel repository, install Xournal again from the Maemo org downloads section, once installed remove/disable the two Chinook repositories it added.

Sorry, but I can't do more than this.
Well I can, just release a working version for Diablo, but right now I do have no time as I am relocating in London to start a new job there.. so.. for a while there will be no update
Shame...

But I will try my best to release a stable Diablo version for Xmas.