I hear your pain.
I have the same issue (as does everyone else I work with), it seems to be a problem in the OSX version of Fireworks.
You can install the following legacy driver it works, but NOT in Yosemite.
- Wacom's legacy driver page
- You want WacomTablet_6.3.1w2.dmg
- Be sure to completely remove the newer driver first
Btw we are thinking of moving to Sketch.