For all people with a lot of events there is a great improvement available. You can configure a page size at the menu item level and show only a limited number of events per page. By default it is set to 12 events per page.
Another feature is the new "cart connector". Instead of displaying the internal cart button you can configure a link which can be shown instead. While it was originally build to connect to an external cart, you can easily use this feature to provide a download button for your image. Check the manual for details.
To update Event Gallery you just need to install the latest version using the Joomla Extension Manager. There is no need to do an uninstall before. Be aware that newer versions will wipe the component folder and remove language files during each installation. If you did code modifications, try to find a better way. If it's just about the language check the manual. I added a section which describes how to do language customization.
There is a manual available here: Event Gallery Manual. It includes a general description of the back end, contains a FAQ section and provides some basic videos.
You want to create a module or a plugin for this component? Get in touch with me. I'm happy to help you out and link your work in the manual.
If you like this component and want to support the development feel free to use the blue donate button in the right navigation bar.