Question in example of "Block Verification Model "

I have two questions on this example,

1) I found that the parametric sweep in this model is like this,
8e-3*{1e-3 range(0.05,0.05,1)}
It means that the prescribed displacement goes from 0 to 8 in 20 steps,
but what is the meaning of the number of 1e-3? Why I cannot write the parametric sweep into
8e-3*{0 range(0.05,0.05,1)}, I tried in the comsol, error shows.
Why the first step should be 1e-3?

2) I am trying to replace the prescribed displacement in the z direction with a dynamic cyclic loading, such as
F(t)=10kPa*sin(10*pi*t), and then add a time dependent "study" in this model, there appears an error, showing

Failed to compute elastic strain variables.
- Feature: Time dependent solver 1(sol2/t1)
- Error: Failed to compute elastic strain variables.

I promise it is a typical and classical error when using plasticity module or soil plasticity module.
At first, I am doubting that that there are some problems for the plasticity module when using time dependent analysis, but after I read this thread
www.comsol.com/community/forums/general/thread/37035/
it seems that my first feeling was wrong.

So anyone can explain to me where does the error come from? How to solve this problem?
Any suggestions from you guys....

Sincerely thanks for all.