Prompt sequence issue

[alex11343]

Hey,

Here's a new issue to solve asap:

I got 4 list prompts on a prompt page

list 1: no cascading source
list 2: cascading source = list 1
list 3: non cascading source
list 4: cascading source = list 3

all prompts are facultative without any automatic submission. the hierarchical relations exist between 1 & 2 on one side and 3 & 4 on the other side.

my problem is:
- when I choose among the available choices in the following sequence 1, 2, 3, 4 -> no problem
when I make my choices in the following sequence: 3, 4, 1, 2 -> selecting 3 & 4 don't cause any trouble but once 1 is chosen, 4 is reset

=> ???!!!???WHY???!!!???

How may I get past that problem or solve it?

I hope to have mad myself clear enough so you can help me the quickest.
It's really URGENT

Any help is welcome, any advice or solution too :)

Thanks in advance

alx11343

note: "2 prompts pages" isn't an available option.