Hi. Why launcher and "what running now" parts are separated? how to make this nexus dock like windows's pinned app to taskbar, i mean i need to make like dont separete this items, show only 1 chrome, when im pressing now on chroms icon (left one) then nexus starting new chrome app, place of current running chrome session

Well, if you want 'like Windows', why don't you just use vanilla Windows?

That said, why don't you explore the Preferences and Dock Properties a little to discover the right settings!? Shouldn't be rocket science. OTOH, Chrome being such a queer app - not to mention such a super-spy on your privacy - there's a possibility that Chrome just won't observe the dock's settings and instead does its own thing.

Assuming you are running the free version of Nexus, open Nexus Preferences, go to the Tasks tab, enable 'Combine dock icons with running applications' and select 'Group similar windows into a single icon' as the grouping method.