Despite all of the above, I did try grabbing a new block chain yet again. Actually, I copied my "good" block chain (from the system that successfully received the SX) over to the other system. The results were the same, so again the conclusion is that for some reason the Import button is "broken" on this other PC. That being the case, let me give a few details of the PCs.
That's the reason is not working, you cannot copy the good blockchain files because Vertcoin Qt-wallet has to scan every transaction in each block. So, you need to delete the blockchain data, and open the Qt wallet, and then lets the program downloads the blockchain by itself.