I am thrilled that DGC is coming back where it once was.  
I can confirm that I was able to restore my paperwallet with the current wallet version easily under macOS High Sierra. I used this release: https://github.com/lomtax/digitalcoin/releases/tag/4.0.1

Also the trading seems to work again and today we have nearly the same price as the TRONix [TRX] coin. :-) https://coinmarketcap.com/currencies/digitalcoin/