Unfortunately, if you yourself called it “a Corellian starship,” some trigger-happy lawyer representing Star Wars might decide that it is too close.
And to be fair, these lawyers are very much driven by a legal principle called the Doctrine of Laches, which basically says that if you do not defend your proprietary claim equally against “any and all” potential infringers, you might lose(!) those rights forever.
When asserted in litigation, it is an equity defense, that is, a defense to a claim for an equitable remedy. The person invoking laches is asserting that an opposing party has “slept on its rights”, and that, as a result of this delay, circumstances have changed, witnesses or evidence may have been lost or no longer available, etc., such that it is no longer a just resolution to grant the plaintiff’s claim. Laches is associated with the maxim of equity, “Equity aids the vigilant, not the sleeping ones [that is, those who sleep on their rights].” Put another way, failure to assert one’s rights in a timely manner can result in a claim being barred by laches. (WikiPedia)
Yes, intellectual property rights can be lost. For example, “dry ice,” “elevator,” and “escalator” at one time were registered trademarks – which were invalidated.
“If you say that it’s ‘a million-dollar race horse,’ but you don’t consistently behave as the owner of such a valuable thing would do, each and every time, then it must not actually be worth ‘a million dollars,’ or perhaps, anything at all.”
So, it’s entirely possible that someone is moving against you because they have no legal choice but to be able to demonstrate that they are not “sleeping” – that they are moving uniformly against “anyone and everyone.” You might well have no alternative but to remove your model and to re-design it so that it no longer resembles a Star Wars intellectual property, and cease to describe it as “Corellian.™”
You might also wish to “contact The Mouse.” What is their policy about such things? Can you ask permission? Do they for instance just want to see a propritary notice of some kind? (To counter the legal horror of “public domain?”)
But – "please don’t take it personally," because it really isn’t. Comply with the demand, then (maybe) step back and contact the Mouse.