A while back YB got me to dl a Minecraft texture pack editor, but we could never get it to work.
Marshalled the mental strength to sort it yesterday (or was it the day before?), found it was the quotes round the path to the editor exe(s) that was upsetting it.
So YB was pleased to be able to edit texture packs.
Then I dl'd something better than MS Paint (Paint.NET) so transparent backgrounds would be, and we were even more pleased.
Except some bits of the edits didn't seem to take.
So late last night had a wander round the Wiki and worked out it's coz they've changed the way textures are handled in the redstone update (1.5) - terrain.png is now only used if there's no png for the particular item, and the app we were using basically works mainly on terrain.png...
So I found the unstitcher utility, converted YB's new pack to the new 1.5 format, and Lo! it all works. Joy unconfined.
And we no longer need that app, we just go into the texture zip, edit the item we want, SaveAs to desktop, then drag back into the zip.
One thing to look into:
The 1.5 release seems to have a few textures missing (eg cobblestone) and the unstitcher doesn't create them. OK they get grabbed from terrain.png but it'd be better to create the files, IF the Minecraft client is going to pick them up, which is open to question as it doesn't have them by default. Maybe they'll be in 1.52