Hi Paul,
- about the galleries : how to change between Testgallery and Testgallery 2 ?
You mean in the module? You change to the other gallery id in the module settings:
http://awesomescreenshot.com/0623duyxd2
In the backend:
You use the select (right side) to change it.
- how toa add an image to one of the mentioned galleries?
You go to the Backend to tile elements -> Select a current elemnt or click on Add (there has to be space for the new element) and fill out the new element data, like the position etc. and click on save.
http://awesomescreenshot.com/0003duzh32
Kind regards,
Yves