To conclude this...
The whole problem was because I use ADE 4.0 and the client ADE 3.0 so I couldn't figure out what is going on on their side.
I set up the chapters to began on new page, so they were wondering why, when chapter has odd number of pages, there is one page on the right to stay blank... And that's how it works...
When I installed 3.0 version, I saw that some images are stretched but I solved it in Object Export options.
Still, the issue with cut images in ADE 4.0 (the reason I started the thread) stays unsolved. It seems that ADE 4 measure both pages width and resize the graphics correspondingly. I do not know how to incorporate SVG wrapper... I need to learn more
Thanks for your help!
Hope I'll be able to contribute to this community soon