Reply to Key Change + Echo Freeze

So two fairly unrelated questions but both involve mapping.

First off, is mapping key changing the same as using the transpose stretch effect (it would be much easier to set up that effect than it would be to change the key mapping). I ask primarily because I would have to create a setup where on pressing down the jogwheel the key instantly resets to 0 whereas I could just do that by toggling the effect off using my S4.

Second, the echo freeze technique is great... but I want to know what parameter I have to tweak to keep that echo going? Is there any way to complete kill its decay, I hate how short the echo lasts and just want it to stick around longer!

Thanks for any input!

Dave