1. Look, this is how animation works in wz4. We must remember that wz is not a fully artist's tool like zbrush.
It has been all around coding starting from wz3 - remember those animation bricks?.. It turns out that animation features in wz4 are just simplified (for a coder)
wz3 animation bricks. So, animation-wise, wz4 takes after wz3 and, alas, not wz1...
2. What can be done? I think 1x splines should be the first to come to the rescue. They are comparatively easily controlled and require just a short line of code: any param=name_of_spline_(time);
On the other hand, some code guru could conjure up a recreation of wz1 animation controls (which I think would be great), but I don't know how much work it's gonna take and who could possibly take this challenge...