Pathfinding
Again, I would say this would all depend on the table chatter.
Guy A: I want Mouse A to go to Grasslake to follow up a contact there!
GM: Okay cool, that’ll be a Pathfinder check.
Guy B: I want to scrounge up some grub and chow so I can get rid of my Hungry condition.
GM: Oh, okay, that’s an Ob 1 test. Guy A, does Mouse A wait for Mouse B to finish his meal so they can go together?
Guy A: Nah. I go on ahead, I’m in a hurry. Besides, knowing Mouse B, he’ll be there in the pub for sometime!
Guy B: Oh, you know me very well, brother!
So in the above example, Mouse A travels alone. If the player decided to wait, then they travel together. Bottom line is the mechanic stays the same, but the story can change depending on how your players want it. Also, the other player, if he tags along, does benefit from the Pathfinder roll (they make it to Grasslake) even if he doesn’t help with the roll, or he can help if he has the appropriate skill or -wises. If he doesn’t or can’t, then that’s okay — if Guy A fails his Pathfinder test, they both get lost, if he succeeds, they both reach Grasslake.
Supplies
Then that is awesome! I would say the dice stack since one is from gear, one is from -wises, one is from supplies, and one is from teamwork! There is nothing magical about this, even if it were the start of Spring, I’d say it’ll only take a while for a harvester to harvest “just enough” that is needed, and the miller would only take as long as necessary to grind it. I would rule AGAINST this if it were called for in my story, for example if the story calls for shortness of supplies or if the Territories just had a very, very lean harvest last season. Otherwise, as the book says, assume they have what is needed when it is needed.
Also, since this is a one-use thing, you don’t have to write it in your supplies/gear section anymore! Not unless you plan to keep it for future use or to deliver it to somewhere else (another city). You can, however, write down the spatula since it’ll “last longer.”
Resources from other mice
I would say that if a player passes a Circles test to find another mouse, or passes a Resources test to find a certain resource (milled grain), then they get what they want. On p.26 and p.127, if a player calls up a friend or his parents on a Circles test and passes, then they are there to lend aid. They won’t have to roll to see if they are able to muster up the “aid,” they just do. For example, if a player stays at his parent’s house, he doesn’t need to roll to see if his parents have food and will be able to feed him, they just do. Passing the Circles test is the “payment” for the food.
While this may sound like having someone else do the dirty work (some other NPC mouse doing the appropriate roll for the PC mouse), then it is! If you want to have a nice wooden table but don’t have the carpentry skill and don’t want to do a Beginner’s Luck, do a Resources test to see if you manage to buy a nice wooden table from a local carpenter. You don’t have to roll for the Carpenter to see if he passes his test, he just does! Your Resources test is “payment” for the table.
Just my $0.02. Hope that helps!