Also posted in the coffee thread - 24hr sale at Old Bisbee - $5 off any 2lb or more order w/ code HOLIDAYS.
Of note - they have the excellent Bali Blue Krishna in stock.
I can't speak directly about the Kontact stuff but my luck with "flux removers" in general was very poor until I tried simple 90+% isopropyl alcohol. I think the alcohol was cheaper too.
Get the purest isopropyl alcohol that you can find in a decent quantity and several sacrificial tooth brushes. Lather, rinse, repeat until clean. Manage the waste appropriately.
It is rare that I get something right like this so I'm happy to help. I also added an edit about the mobile icon now being different for new/unread content.