Not an expert on trading, but I am pretty sure you would need to get someone to lend you some NMC. Then sell that NMC at the highest price you can, wait for the price of NMC to go down, purchase back the coins and repay your lender. The coins gained would be considered a short. Again not an expert, hope that helps.
That would be shorting the old fashion way. Only problem is that what if they intentionally make themselves unavailable during a spike...
I want to trade on a liquid market...