dvjames,

Short answer- You're fine to follow those instructions.

Long answer- Extras-Devel is a repo for packages that are for development, are being tested, or are considered 'not ready for general distribution'. The danger with leaving the repo enabled is that it could allow you to install unstable apps or worse, allow you to upgrade packages from a stable version to an unstable one.

However, some apps you want might only be in Extras-Devel. In this case, I think xournal only needs a shared library from Extras-Devel.

As a Xournal user I'd recommend installing the app, then disabling the Extras-Devel repo via the application manager. This will give you xournal without making your system unstable. This isn't *hacking* the device. (Chinook aside, with the current state of Diablo repos, there are more than a few stable apps that haven't made it to either repo simply because they don't autobuild...)

It is a good idea in general, to only enable extras-devel when one wants a specific package (such as Xournal) then immediately disable it afterwards. This prevents the application manager from trying to 'update' you into an unstable state. Make sense?

hope this helps,
kernelpanic

[edit]p.s.- to disable repositories, in the application manager menu, goto Tools->Application catalog. You'll see a window pop up with the list of repositories. look for 'extras-devel' and click 'edit'. look for a 'Disabled' checkbox and click it. Then press 'ok'. You're done ;-)
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