Hi fellow Boomers.
I had downloaded "Lilly" from GOG. When I started playing the game, it was VERY, VERY slow. I contacted GEETA GAMES SUPPORT, and they replied immediately.with a solution as follows:
Download and play the Lilly DEMO. Right Click on the screen and you will get a small window called ADOBE FLASH PLAYER.At the bottom of THAT window, you will see some small boxes. CLICK on the left-most small box and you will get another window that says: "Enable Hardware Acceleration". If the box next to it is blank(as was in MY case), click on it and you will see a "checkmark" in that box now. Close the DEMO and then restart your FULL version of the game. IT WORKED!
This might help some of our fellow Boomers who are having the same problem with this game that I experienced.
Sandy