Initial Installation 
For Windows and Mac OS X, simply download off of the download page, extract, and run. The first time MCJ is run it will create a fresh database in the same directory as the application if it doesn't already exist.
On GNU/Linux is a wee bit more complicated. Download the tarball file off of the download page, extract with tar/gzip, and make sure mcj has execute permissions.
Since this application is a single executable, simply delete the application to uninstall.
If you are running a version prior to V 2.0, you will need to import your journal entries (back them up first) into the new version by entering your import prefix (journal, probably) on the Entries tab in File/Utilites and Settings, and clicking the Import Entries button.
Journal
