Click the green flag to start. Before you start drawing a sprite, edit your precision. A higher precision means the computer saves information more frequently, which increases the quality of the sprite. If you want to draw a sprite, you can press [space] to toggle recording. When you are recording, the computer will monitor and save the position and colour of the pen, and whether it is drawing. To draw, hold [click] or [leftMouseButton] and to change colour, saturation and brightness, use the sliders. If you want to pause the recording, you can press [space], and press it again to resume. Once you are content with your sprite, stop recording with [space]. [shift-click] the green flag and press [E] on your keyboard to toggle use of the sprite. You can move your sprite with [arrow keys] and change the size with the slider. Press [C] on your keyboard to clear all data about your sprite. You can then draw another one. Remember to press [E] and [shift click] the green flag again. Press [V] on your keyboard to change view. This will toggle which sliders you can see. If your parts of your sprite start flashing or don't get drawn at all, it means there is not enough time to draw the sprite out before it needs to be redrawn. You can press the green circular button to downgrade the quality of the image (may lead to corruption) or turn down the tickrate (this will make it less responsive).
If you have an idea for the simulator, please comment it, and I will try to implement it.