An update.
Yup, I haven`t forgotten about the contest but was distracted by work, illness, a home invading sleepover birthday party, a pulp freighter build, a pod colony build and a few other tidbits.
After many an unsuccessful attempt to build some curved staircases (too ambitious for alloted time) out of my chosen mystery build material, scraped what I had done to date and changed to something a little more conventional. Lots of lessons learned at least

and gained a nice pile of warped plexi

.
Here are the new templates:

And stairs cut out:

The main landing built up:

Gluing the stairs in place:

Also started on the columns:
More to come.