Seems like a good plan. Differentiating from the Summer games adds a bit of variety and the collaborative aspects should make for some interesting results.
A single track will work but I think we’ll need to provide more guidelines on what we’re expecting otherwise we could end up with anything from a single PowerShell pipeline aliased beyond all recognition to a windows form type application that involves 100s of lines of code. Judging that spread would be challenging
I like the idea of the coaching – should be interesting when the coaches don’t agree 
The Summer games had a 7 day event period if I remember correctly. So the timeframe seems about right. May want to add a couple of days to group activities as I suspect that in many teams members will all be from same organization & may not be able to get together on a weekend
Please include me as judge & also willing to create scenario (cue cackles of evil laughter…)