Both the free and the pro version of the shoutbox are released under the terms of the GNU General Public License, version 3. This license allows you to install the shoutbox on an unlimited number of websites. Moreover the Pro version of the Shoutbox will continue to function after the expiration of your subscription. The Shoutbox is an Open-Source extension.
Of course you can! But you will not be able to download new releases and submit support tickets.
Yes. Shoutbox Pro is released under the terms of the GNU General Public License, version 3. This license allows you to install Shoutbox Pro on an unlimited number of websites.
No, both the Free and Pro version of the Shoutbox only run on Joomla 2.5.5 or above.
No, the subscription will not automatic renewal. It ends automatically when the membership duration expires. You can renew your subscription manually before expiration.
The requiremens for PHP and MySQL match those for Joomla itself.
You can install the Shoutbox like any other extension. If you can't find the module in the module manager, create a new module and select shoutbox. Select a position and publish it and you are ready to go. Note that if you use the Shoutbox Pro that you have to create a category for it first.