Hello,
if you still have this problem and are using a laptop, try to plug a usb mouse before starting the game. it worked for me.

I have exactly the same problem on Syberia 1 and Syberia 2. I can move the mouse over buttons and they'll light up, but nothing happens when I click. Does anyone have a fix for this?

Same here, is there a way to play it with just touchpad on a laptop?

Ok, found how to solve it on my Thinkpad x230. Compatibility mode: Windows Vista and USB mouse

I've been having the same issue too, except mine is even stranger.

Sometimes when I boot up the game the mouse clicks just don't register at all. And other times, for about 5 seconds it kind of works but then it just stops again.

I'm using a Windows 10 Lenovo laptop with a USB mouse. I've two computer mouses (mice?), I've tried compatibility mode, I've tried restarting my computer, but it still refuses to work. And it's frustrating since for the first 5 seconds it works but then it stops. I end up having to press the Enter key to leave because I can't do anything.