MedicalStore: thanks for full responses.

Block Roll: good idea, I'll look at adding more cues for blocked actions.

Clockcheese: I sort of had the feeling the control might be difficult. On a desktop/mouse, it is intended that the user would just drag the mouse (left-button down) side to side across the bottom quarter of the screen. Similar with touch screens - drag finger back and forth along the bottom. The wheel will always drift, and will continue to at the speed at which you last dragged it. The object of the game is to move the wheel so that no part of it hits the mouse. Let the mouse get the cheese, which gives you stars to collect. I'll see about making a video.

I think I can see people might want to turn the cog by literally dragging on it like a real world object. The reason I didn't implement that is because your hand on mobile devices blocks view of the play area. Thus I restricted control to just the bottom of the screen. I guess I have to work out another way, or offer better instructions.

Thanks again. It was a great help.

I made a game engine that might suit your needs - it is intended for small sprite-based games. There is nothing to download, but there is a new language to learn. I think it is simple enough to learn from example. There are lots of demos on the website and since this is relatively new, I'd be happy to work with you to get you started. The site is http://structuredcanvaslanguage.com/

You code directly onto a textarea of the web page and push run. On the site in the "try it" area you can try out pacman, space invaders, and others and tinker with the code right inside the page.