The lucky rock is an in-app purchase (IAP) which can only be obtained by paying real money. There's no equivalent to the App Store in iOS (which provides the mechanism for IAPs) for Windows or Mac OS so the answer to your question is most likely no. Anyway, you've already paid for the game, so being asked for more money would be seen as something of a cheek by most people.

There may well be an update to the game, but judging by past updates to LDW Windows/Mac games it's only likely to contain bug fixes and the like, not new features.

That said, updates to iOS versions have contained new feaures, but that's released under a different ('freemium') model.