My understanding is that masternodes are meant for PoS coins only. Kryptohash is a pure PoW coin. Honestly, I haven't looked into masternodes at all. I have my own ideas that I want to develop for this coin moving forward.
Also, I really don't understand the need of InstantX. Not even with credit cards you get instant transactions. The only thing that it is "instantaneous" with credit cards is an authorization code that just tells the cashier that the card isn't in the black list or above limit. At the end of the day, the Retailer gets a final tally detailing which of the transactions that got authorization code are approved and which ones are rejected. I know this because I used to work developing SW for POS 15+ years ago.
Finally, with PoW coins, having Instant transactions is calling for unnecessary trouble. Bitcoin has 10 minutes block time for two reasons. 1) The accepted blocks take time to propagate through the P2P network and a block might take a good 2 minutes to reach every corner of the World; 2) Each entry of the blockchain consists in a header plus the list of In and Out transactions. Reducing blocktime increases the usage of HD Space. It is less efficient from the storage point of view, since you are storing too many headers for only a handful transactions.
I believe 10 minutes is too long so, in KHC I'm using 3 minutes. Anything below 2 minutes is just synonymous of trouble.