I am sorry to hear you can not get your problem resolved. I hope it gets corrected soon. It is not easy plopping down the kind of money we do for this hobby in these times.
If I were you, I would sell it, and opt for an SRO, SWC, any company here in the states. Warranties are one issue, but what if your pump is not covered? What would it cost to replace it? The pump is the heart of the skimmer. That 3 year warranty on my SRO pump really sealed the deal with me.
I have bought some items from Aquacave, just for the price point. However, one of our sponsors here, Premium Aquatics, meets or beats anyone elses, and has excellent customer service before and after the sale. You can verify that by their forum here and what people have posted. Same goes for Coralvue.