It was worth the wait...
My felted bag has turned out wonderfully. A really great size, shape and colour. Thank you, Secret Pal, for the tools and advice to do it.
It was interesting how it changed shape - before felting it was long and thin. Having read about Di's experience of getting mangled lumps where the edges roll up, I was really worried about the gape of the handle.
I ironed it over and over again and it refused to flattern properly, but in the end it turns out it's part of the design and the cast off bit stays straight, while the newly cast on stitches over roll up to form the handle better.
My front-loading washing machine won't let you stop it part way through, but it seems to be quite accurate as to the temperature you set it to (which I can do independently of the programme). I put this through a quickwash and set it to 50 degrees C.
I had worries about it felting the front to the back so put one of DD's t-shirts inside. Watching it through the window, I saw it fall out almost immediately and there's no sign of any sticking. I also washed it with a couple of towels to bash it around properly.
I'm kind of sad to have lost the really soft texture of the knitted wool (that wool is really lovely), but the felt is really strong - I can use this as a proper bag with no worries of holes appearing.
My only problem was I ran out of the lighter coloured wool, so one side is different to the other at the handle. But because of the quirky texture of the felt, it actually looks pretty good like that.
The colour didn't fade or change at all (just the light changing in these photos).