Duplicate movie clip adjustments

[symbolica]

Hello,

I have found a little FLA which demonstrates how the duplicate movie clip can be used.

I tried to simplify and adjust the AS according to my needs. With some part i was successful but with some i wasn't.

My first problem is,
i want to be able to set the beginning X position of the clips as "0" in X values. but when i assign "0" to the this._x , it naturally generates/duplicates all the clips at the same point. What I'm trying to achieve by doing this is, when the stage is scaled in means of width my clips should start to originate from the very left of the stage whatever the stage's width is.

my second question is how can i adjust the speed?
When I stretch the stage width they(duplicated clips) all speed up in order to travel the whole stage in the same amount of time as they do with the initial/beginning stage width. I want the speed to stay constant whatever the distance is.

I'm sure you'll have more idea on what I'm talking about if you can take a look at the attached FLA. You'll have a better idea about my intention.

THANK YOU ALL,