Maya Cycles, Pole vector value switching and Undo not working

Hey peeps, long time lurker first time poster!
I created an Ik/Fk switch using a single chain which was shown in Sylvan Cote’s master class at area autodesk.

I was hoping some one here could help me out and explain how to fix a few issues created for myself.

When switching the ik blend from 0 to 1 the pole vector pops the change in value is so small you’d never notice it during animation but it’s really bugging me, anyone know how to set the X,Y,Z values to 0 in both instances?

I think it has something to do with the locked pair blend node but I’m not 100% sure, I’m still pretty amateur when it comes to more technical rigging in Maya.
#FIXED (Updated the values on the pole vectors parent constraints)

The other issue I have is when is in fk (Ik blend = 0) whenever you move ctrl_L_ikHandle and attempt to undo the movement you get a Maya cycle warning which as far as I know shouldn’t happen.
It’s not a major issue as I can just create an fk hand controller (which controls b_L_hand) but you know it would be nice to not need to.

Also is it possible to swap out the nurb circle (ctrl_L_IkHandle) for another object and still maintain all of the connections?
#FIXED Many thanks to Vertigoo on the IRC for the tip
I removed all the connections to the nurb curve via the hyper graph, went to the script editor copy and replaced the disconnectAttr with connectAttr bit of renaming and bam!

All of the problems are just quality of life/easier to animate, other than that the ik/fk switch works fine all that is needed to switch is that the entire chain is keyed on both Ik controllers and FK controllers.

Many thanks!

https://dl.dropbox.com/u/16595242/Webhost/arm.ma