I don't know if it's still relevant to you, but I discovered how it works.

Simply press any of the arrow key to make the sidebar appear and click on the cog. You'll then be able to drag and drop your dinos in the new window. Save the changes.

When you want to recover one quickly, open the sidebar with any arrow key, navigate through it with up and down, and select a pokeball with left or right.

that does help a lot but after the save I can't do it again for some reason so I have a stuck party. Thank you for the reply.

click on the cog doesn't work