Ok - I've now done the gingerbread. That's a puzzle that definitely needs better clueing - it's not at all obvious what needs to be done. It would make a big difference, I think, if the gingerbread was visible up there on the top shelf rather than the player having to have faith in what Mrs Claus is telling you (or maybe I should just learn to be more trusting). It might even help if it was visible in the picture. I found myself confronted with the image of empty shelves thinking 'is there really any gingerbread up there?' and then trying various ways to clamber up the shelves, to no avail. Part of the issue is also that this is the only puzzle where something that you've already made is involved - I had a bit of a blind spot that I had to take something back off the sleigh and use it; for me, once the toy was made and loaded on the sleigh, that was the end of the process and I wasn't expecting to revisit it.
As for the flipping light source - still can't fathom it. Presuming that what is involved is the fire in Santa's living room (as I can't find a way to get into the bedroom): I've examined everything and attempted to set fire to everything (including all products of the wood store) but no joy. In the end (and as an indication of my desperation) I was reduced to attempting to undress Santa as he slept in his chair (partly for kicks, but mostly because I thought there might be something in his suit), which produces a couple more bug responses: GET BELT = 'you can't see that anywhere' and UNDO BELT = 'rewind is expected as a single word' (interpreting that as the standard UNDO command). So I'm still stuck on 90/100.
Glad to see that more location graphics have appeared though - I expect that when I get back to it again (having figured out the light puzzle) even the metal store will have a picture!