Thanks all,stripped it back out and cleaned,washed and dryed the area(hairdryer)siliconed the holes,refitted the spoiler and put rubber washers over the bolts on the inside before the steel washers,also put a band of sticky foam all around the edge of the spoiler and got a better fitting gromit for the brakelight.....looks as if it should have done the trick.
Used an Aquavac to hoover out all the water and dried all the interior of the boot....only thing is the wheel cover and carpet smell of dampness so they're getting a good airing at the moment.
Hopefully that will be the end of it,cheers.
Del.