I think the idea of the time sensative launch Simon, is to stop the paint fully curing, thus stopping it doing what it says on the tin? I think the worst that will happen is you will have more 'Clingon's' than you would, had you launched it on time.
It certainly won't like starting without heat! If it will at all. Thats why testing the position 2 when the engine is cold should give you a definative answer. The other way of course is to turn the key to position 2 and see if there is current flowing to the plugs with a simple test meter or even a 12v bulb held on the plug contact with a short length of wire to earth to the engine.
In that case I think you will have to test and see if Pos. 2 is heating the plugs by trying it on a cold engine. turn the key to pos 2 wait for 15 seconds and then go for the start. If it fires up straight away, then do as the instructions say and turn the key to Pos4.
Washing up liquid is brilliant to use as a lubricant when fitting a new impellor. I do of course replace the cover and start the engine within a matter of minutes, so it setting has never been an issue for me