I noticed that all of a sudden the way scrolling in Modern UI works has changed.
I would use a two finger swipe (top to bottom) to move through the Modern UI, regardless if the content is actually scrolling horizontally (ie. left to right like the App List), or if the content is actually scrolling top to bottom as well (like the chats in Skype).
A few days ago I noticed this changed. Now I have to actually do a left to right two-finger swipe to move through the Modern UI content, regardless if it's actually laid out that way (the App List requires this behavior, which sort of makes sense, but it's super annoying in Skype because it feel more natural to swipe from top to bottom there).
I installed the latest Elantech drivers when recently reinstalling the OS (Windows 8.1), but I can't seem to find the multi touch settings tool. And I'm certain it behaved differently in the beginning (top to bottom swipe to scroll both horizontally and vertically) and that this is a recent change.