The downloadable file is the full version of the product and is meant to be installed in trial mode. That is, the demo and full version feature the same reporting functionality. If you decide to purchase the product, you do not need to uninstall the demo, you merely need purchase a license code from an authorized reseller. The demo license is free, and expires after 30 days.
Incremental upgrades (number to right of decimal point) are always free. If you are upgrading from Urchin 5.0 to 5.1, for instance, it is a free upgrade -- your existing license will work.
If you are upgrading Urchin 5, please review our upgrade instructions in the Urchin 5 Help Center before installation.