I fell in love with a Timber Frame house a few years ago and bought it. Now that I've learned much more about it's structural details I see I've got (more than) a few problems. I'm asking for realistic advice on these issues and how can they possibly be addressed now. I've got a shop, youtube and plenty of DIY in me. While the fixes may be overwhelming, I am willing and able, with the help of friends. Thanks in advance to all who can answer. Graphic attached.

The Problems:

Q:Where is that cold wind coming from? This is an envelop timber frame SIP house. There do not seem to be any 2-x plates topping the curtain-panel walls. The Walls do not meet the roof panels by about a 2-3" gap - see graphic.

Q:What are the scratchy sounds and why are there styrofoam beads on my floor? Mice have colonized the gaps and maybe the walls. There is not enough room to get traps into the voids and i fear my cat will eat half-dead mice.

Q:There is NO building paper on the exterior of the OSB walls. So how can I pressure wash and stain this house? Is it possible to remove the cedar siding and paper the house?

Q: The skylight surrounds (casings) are dropping out of the ceiling. There is no framing ( 2 X Let ins) around the skylights. Can I add that now?

Q: Why is the builder of this house out of business?