That's extremely disappointing. I've been a paid FlexRAID customer since 2012, and I have enjoyed the product and recommended the purchase to others. Even after I asked if the loyalty upgrade was still available and you said no, I still bought a full license on the merit of your products' past performance, without full testing, as I was confident the quality of your products would serve my needs. My setup and testing process took much longer than usual as I have just moved house. When Windows turned out to be problematic, I checked the tRAID purchase page to see if there were separate licenses for Windows and Linux and found there was only one purchase link for either; even clicking "Buy Now" just initiates the PayPal process rather than prompting for details on the host OS. So I had assumed the license was portable. I have now wiped out Windows, and spent a week transferring 18 terabytes of data from NTFS disks to ext4 disks, and I find out I'm left in the lurch. You're basically saying "ha, I've got your money now - too bad so sad."
So I'm faced with moving all 18TB of my data back to NTFS and taking another dubious stab at Windows, or just accepting that I basically lit a $100 bill on fire and trying to find something else. Given the lack of service on offer here, I'm heavily leaning towards the latter. I've confidently recommended your products to several friends for their home servers in the past, and unfortunately I won't be able to make that recommendation in the future.