MouseController is a tiny portable tool (a 63KB executable) which can record your mouse movements and clicks, then replay them later.
Launching the program displays a basic but straightforward interface. By default pressing F9 starts to record your mouse actions, but you can change this to any other function key. Press your choice whenever you like to begin recording, then use your PC as normal, pressing the hotkey again to toggle recording off.
A "Start Playback" button tests your macro immediately, and worked well for us: the cursor moved around, repeating all our points and clicks without difficulty.
Your macro can be customised in various ways. MouseController can replay it at different speeds. There's an option to display the number of every click, as it happens, perhaps useful for demonstrations. You could automate some action by having MouseController repeat its macro every few seconds or minutes, or for a fixed number of times, and there's even an option to launch it from the command line via your own scripts.
This kind of mouse automation needs to be used with extreme care. MouseController doesn't know what it's clicking, and if your system changes before playback - there's a different screen resolution, other windows happen to be open - then anything could happen.
If you understand the risks and work to reduce them, though - perhaps maximising one program window and closing everything else - then MouseController works well enough, and may be able to help you automate some common tasks.