For example, buy an alt-coin at price X or one exchange and sell it at price Y on another?

I have no experience as I've only ever used Poloniex. As a variation, I've foolishly bought some very thinly traded coins e.g. CNMT and am wondering if they is a way to dispose of them outside of Poloniex (where there are very few buy orders).

Any suggestions / ideas / thoughts?

I bought a small amount on Poloniex some time ago. The BitX environment strikes me as innovative and forward-focused.

However, the volume of BitCNY on Polo is dire. Amazingly, today there has been volume of almost 1 BTC. Usually it is about 0.2 BTC.

Can anyone please tell me what is going on? Why is this coin so under-appreciated? Many thanks!