I'm not sure if this was covered in one of the links, but this routine *really* helped me (I had chronic, wicked plantar-f):
30second walk on tip-toes, 15seconds in each direction; repeat while walking on heels; repeat while walking on tip-toes with feet turned outward/inward; repeat while on heels. Work through some controlled ROM stretches with the calves. Finish with full-extension standing calf-raises.
I tried insoles/orthotics and a dozen other things and the problem still vexed me. The above, though, worked amazing...surprisingly well....for me.