I gave it a trial run. It is a pretty good reproduction, albeit there are rough edges that make it an imperfect replica of the original. I have compiled a list of 20+ things that I believe are different from the original game (which I have played extensively), and or/buggy. @Developers - I would email it to you, but you don't seem to have any contact information anywhere, and I'm not sure I want to fill the comments section of your pages with feedback and bug reports that others might take to imply that the game isn't that good. If you are still around, please let me know how you would like to receive my report. If it is satisfactory, I can also make a video that points out some of these bugs in live action.
At any rate, I've always thought Greebles was a marvelous, underrated Mac game. This port already captures a large amount of what made it great, and with the flaws fixed, there's no reason why it can't be fully successful in reproducing the original experience. Classic Mac ports are a worthy endeavour generally, and this is an especially worthy game to port, and it deserves more public attention than it seems to have gotten so far.