Tried to post this at the end of the week but got some sort of error. Anyway, better luck this time.
I've made a bit of progress with Wellies over the May Day weekend, based on the feedback from the Beta-testers. Firstly, a new control panel with a bigger launch button. I've also sorted out problems with the collision detection (was only detecting in the horizontal but now deals with the vertical as well). Also put in a loop back to the start to save relaunching each time.
Additionally I've been thinking of some new weapons and have thrown together some graphics for a carrot torpedo and a spade (can you dig it?) but have yet to decide on their effects (though the carrot will almost certainly NOT spin, but fly tip first).
Here's a screenshot with the updated control panel.