Confused...what's the advantage to the electronic shutter release? Doesn't it eliminate the benefit of MLU, which is why we use the dual cable releases in the first place?
with a leaf back, the only advantage of the electronic cable from camera to back is that you can trigger the RZ from your tethered mac with LC11 via fire wire.
it might be helpful in live view mode, but you have to control focus, shutter, aperture by hand anyway.
mirror lock up does not work from the computer, nor with any electronic release (IR trigger etc)
like in film days, you need a mechanical cable attached to the lens for that.
so the electronic release is no substitute for the RZ dual cable release, as you indeed loose the mirror prerelease.
the electronic cable can be used with any lens.
to use it with the t/s adapter, you need the right angle connector, that comes in the box, together with the t/s adapter.