Thanks for that Drew, I was thinking of giving you a buzz, the other question was - did you fit the strip into those spring clips that are fitted into the inside of the window frame at the bottom, just like the outer ones are, or are the rolltops too thick. Nice idea as I stapled my strips on and they're not holding up that well so sounds like this might be more secure. I was also thinking of getting plastic strips with felt glued on as they would be easier to staple but your suggestion sounds better.
Cheers,
Len