Found the problem. It was pretty complex but i will try to explain (the cause is my not fully matured knowledge in B4A stuff).
I have a main activity with a layout, CREATED BY DESIGNER, where there's a fixed top panel of 50dip (Height = 50 set in designer). At bottom of this Top panel i have the MAIN panel which take the all remaining 100% of the vertical space where i load inside other layouts making them to slide showing several contents, based on user preferences. Where i load these layouts i using as top the reference as 50dip BY CODE.... and this was the problem!
With difference screen resolution/scale, (i had tested just with 320 x 480 the changes i did through CODE and not Designer) Android scaled the JUST views it takes from layout created by designer.... so the 50dip i had set in designer, in CODE lost its reference regards those views i add dinamically using the constant 50dip. There wasn't a full reference, by the 50dip height i declared in view in designer and the 50dip i used dinamically in code as reference to set coordinates for other views. I moved to remove the reference of 50dip in code and i used TopPanel.Height reference or other measure that is calculated at Runtime. And everything worked fine.
Conclusion: what is scaled by Android that is CREATED by Designer, it cannot be used as measure reference for views we add later in code except we take their measures from Runtime-calculated values; using the same constant we declared in Designer, in code, get wrong and unexpected results.
Now i know. Thank you the same Erel, and forgive time lost.