Richard,
I ran a similar job today KMCY and it looked much better, so will be doing that from now on..Awsome inks, I'm using about 25%-35% less ink then the previous ink I used to use..Its also more vibrant and glossy.
I have noticed though that its ink/water latitude window is narrower then the other ink but I can put up with that.
we are using with great results
Bottcher 3004 fount 2.5%
IPA 3%-4%
water hardner .5%
RO water.
and printing on polyester plates with zero ink pilling and fantastic screens.
Next step is to reduce the ipa to 2% and see if we can go ZERO IPA.

Meny, I agree with richard, are you sure you havn't got your IR up too high.
I've had mine on for every job so far with this ink and no problems. I set it so the stack sits at roughly 32.c - 35.c

ph 4.5, minimum of alcholol substitute, as alcholol subs contain glycol ethers which inhibit drying, pile temp at 95 degrees farenheit, and app 25 micron spray powder. coating is prefered but a good hard dry varnish will work too
ive used this combination succesfully on silk and matte coated stocks with stay open inks and no drying problems