Is it the Chronicles theme that's missing the UI elements for adding attachments to posts?

They are disabled, you can activate them from the admin panel <!-- s:) --><img src="{SMILIES_PATH}/orc2.gif" alt=":)" title="Smile" /><!-- s:) -->.

I've tried setting stuff, theoretically now admins can post attachments, but standard users can't. Will need to be tested.

When you reply, if you use the full editor, you'll see the upload attachment panel, where you can select which files to upload, so it seems to work fine.

After fixing the permissions on the upload directory, now it actually does work.