(I tried to click on quick reply, yet it didn't work, anyhow, this is to answer this thread question)
As far as I have used it, the dilithium exchange is Great, all I do is choose to trade my crystals for whatever the cheapest amount is being offered at the time, and it goes through instantly.
The only time it doesn't is if YOU offer a price (an amount of crystals per zen), which is Not being offered (displayed), at the time.
This is very simple to me, and yet I am still very new at this, and do not understand any confusion over such an easy and great system.
Fact is, to have a chance at receiving zen, in exchange for crystals, I think is worth whatever the lowest price of the day.
Better than getting no zen I say.
Anyhow, yeppers, just put on offer the lowest that you see being offered, or you shall never receive zen. I for one am grateful for those trading zen!!
These kind people spent real money for zen and is offering it up for free basically, (and of course lots of time spent on missions to get crystals), if they wanted to offer 1 zen for 200 , I'd understand.
So let me be one person to say here, thank you people whom offer zen for crystals, for without you, someone like me (whom can't afford to pay real money) could not get zen.