Hey stephenmuss - thanks a lot for catching this, seriously appreciated.
Harboria is the biggest project I've released so far, and somewhere in the routine of publishing steps I slipped up on packing the meshes properly. The archive went out incomplete - my bad.
A fixed update is already live and ready to download. Grab the new file and it should unpack cleanly. If anything still looks off, just tell me and I'll sort it right away.
You're also very welcome to join my Discord if you'd like support or just want to poke me directly - I keep my hands on the cockpit at all times.
Thanks again for the heads-up!