thanks for making suggestions. While it may take a while to incorporate them, there is a half-manual way to do the repeating game with the same card setup.
First, you have to write down the 10 Kingdom cards of the game you want to repeat (can be on paper, but better would be in some text editor on your PC.
Then, you can create a manual game by going to the "My Table" tab, click on "Create Table", then "Select Kingdom Cards". Here you can select the cards by clicking on them, *but* you can also enter a comma separated list of card names in the text box (see attached picture). This way, you can paste the prepared list of cards into the text box at once!
If you start the game now, it will have the Kingdom you specify. Even better, once you've finished the game and are at the end-of-game screen, if you click "Ready", it will again be the same Kingdom setup, so you can repeat the same Kingdom and refine your strategies for as long as you want.