Scratch

Hi richi07,

open the project in your web browser, then click on the "Add to gallery" link, which is right below the Love-it heart. Then a dialog box with all your galleries pops up, in which you can select which of your galleries you want that project to be in. If you don't have any galleries yet, first create one ;-)

Does that answer your question?

you can put any Scratch project you like into the galleries that allow you to add projects to them. But the project's creator can always remove them again (they usually don't, though).

Many galleries are set up to be personal galleries, where the owner acts as editor, choosing projects to add and adding them him or herself.  You can't add your own projects to such galleries, though you can put a comment on the gallery, suggesting that the owner consider adding your project.

A few galleries are set up so that a small group of the owner's friends can add to the gallery.
This mechanism is not well thought out, since the owner cannot have different groups of contributors for different galleries.  I suspect that this mechanism will change in the next year.

Many galleries are public, where anyone can add, but only the project owner or the gallery owner can delete projects.  If your project is on-topic for the gallery, you may add your project to such a gallery. (Gallery owners may delete your project if they feel it is not on-topic.)  You do not need to ask permission to add to a public gallery, as the owner has granted such permission by setting the flag that allows anyone to post, but if you post off-topic projects, then the gallery owner will be rightfully upset with you.