I do have the woofer enclosures together and working now. Originally I had the baffles in the corners, slightly toed in, with the enclosures between them spread out by around a meter. I've now moved the front baffles out into the room so they're about 1m from the back wall and about 15cm from the side walls with no toe-in. This sounds quite a bit better, but it's still not sounding good yet.
I'll try the felt pads you recommended, and I'll also see if I can find an area rug to go on the floor and maybe put something on the wall between the speakers and directly behind my head. I'll let you know how that changes things.
Thanks
Gary