Hi!
1) Is a repository required on my server, or is MW
just download from
an SVN repository?
No, just a 'check out' or 'working copy', that is, what you create
with 'svn co'
2) If a repository is to be created on my server, what
is a good
folder structure? Right now MW is on c:\wiki\MediaWiki\MediaWiki
1.6.3. Should the SVNRepository folder be created under c:\wiki?
Repository will contain files as they appear in mediawiki-1.x.x/
directory in tarball.
Moreover, second argument to checkout is destination path. You can
name it however you want.
3) Once SVN (and maybe a repository) is setup and MW
downloaded, how
are existing modifications to localsettings.php, any added extensions
in /extensions and any peer folders, such as wiki/SSOLogin
incorporated?
LocalSettings.php is not in repository, therefore it won't be
overwritten.
If you do any changes to other files, they either:
a) merge properly with changes done to main repository
b) raise a conflict, so you have to fix it yourself. It doesn't
happen if you're not editing files directly.
Any files that are not existing on repo will stay intact. It may be a
good practice though to use out-of-mediawiki-root place for your
extensions. Anyway, at least have backups.
Domas
P.S. if there's anything useful in my message, it can all go to
mw.org