Yes, been to KBP at least 16 times this year
AFAIK, The lounges are independent, so if you show any elite level membership card you should be admitted right in (Play a fool and say that you pay extra for business lounge access - they don't usually know the difference - in case she gives you a tough time just slip her a $10 note and you should be fine)
The lounge in Terminal B used to have free wifi, but last time i had to pay (not sure why)
Terminal F also has a decent lounge (By eastern European standards)
Terminal D (Still under construction) Will have a few nice lounges.
None of the lounges have showers or anything fancy that we often see in western European airports