Hi Rozek,
so, there isn't a block to call with a specific ID, but I should use the callback shortly before I use the show reward. I'll try for it asap the extension is compatible with the new version of Stencyl, because as I reported, when I compile with this extension, the project have some errors that stop the compile job, so I cannot test the game and the extension.
It seems that the extension use the same name package as the project.