What you've basically said is "I don't agree with your opinion, therefore you are wrong". While you may have provided justifications for your beliefs, your delivery was unnecessarily aggressive and only served to further alienate yourself from the discussion. I would encourage you to try and engage in more constructive conversation in the future.
For what it's worth, I also despise this sort of needless UI fluff for essentially the same reason they do; it reduces usability.
> UI elements that move around are bad for usability
Bit of a broad brush here. When the "next ->" button moves around of its own accord (in response to changing text content, say) and you need to click it to page through 10 screens of text, that's for sure bad. When elements move in response to a toggle the user clicked when they are nowhere close to the elements that move that's really not a big deal in my opinion. This is especially not-bad when the toggle will move everything back without the user moving their cursor.
Consider the "Backup verification" window[1]: The whole window is overwritten with a readme upon clicking "More on this...". This is bad, I've seen more than enough people X out of such windows (because they think it's not the window they were working with) and then wonder where the window they were working on went.
Why couldn't the readme open in a separate window? It's completely different contextual information to the window they were working in, and in fact most software do produce a new window when opening help documentation so users aren't confused. Different windows for different contexts, this has been standard design for windowed environments since forever.
Now consider the "Backup settings" window[2][3]: Why are the various dropdowns a button you click on which proceeds to resize and move the entire window?
Standard design for dropdowns have always been dropdown menus. Almost everyone knows how to use dropdown menus, both Windows and other programs use them. This is inconsistent design language for the environment the software operates in, and this is confusing for users.
What's more, there is no scroll bar to indicate there is information overflow in the window[2]. Can you tell there is more information above the "More options..." section in window[3]? I know I can't.
We need to take a page from Apple's playbook on this: Consistent design language is good design language. In this case, follow the design language of Win32 and Windows in general. Yes, this isn't as easy as it sounds since Microsoft themselves violate the rule of a consistent design language, but that's not an excuse for others to also violate it.
Not presenting a scroll bar to indicate information overflow is also inexcusable. A user interface exists to inform and guide a user, hiding or even lying to the user defeats the very purpose of a user interface. On that note, the window is being resized, why then isn't it being resized to show all of its contents? At least the resizing would then have a legitimate reason.
Now consider the "Preferences" window[4]: Why are the help texts for this window hidden behind "?" when the other windows either don't have them [1] or show the help text outright[2]?
Why is the "More..." text a hyperlink and the "Less..." button a button when they are the same interface element? This criticism also applies to the "Backup verification" window which exhibits the same problem.
This is all inconsistent design language within the software itself, let alone when compared with its operating environment. This is bad, again: Consistent design language is good design language.
For what it's worth, I also despise this sort of needless UI fluff for essentially the same reason they do; it reduces usability.
But that's just like, my opinion, man.