Spring RTS Engine

I have a laptop with Optimus (NVIDIA+Intel card) and a monitor connected to HDMI port. The OS is Arch linux. Currently I am using bumblebee and have output on both laptop screen and monitor. The outputs are independent X servers created by bumblebee (not my choice, could not make the monitor output without bumblebee, and bumblebee uses one real server - the laptop screen and a 'virtual' second server for the monitor). To handle the input across, I have synergy.

Now, the problem is that spring + synergy does not go well. I have found that people had some time ago with sdl input and synergy (guess spring is not upgraded to latest sdl): mouse "lost" after pressing a key.

The question is: is there anybody with similar a setup that has any suggestions on what I could try to make it work?

Finally solved it. Just for reference I post here the solution: got a VGA cable, seems that it is not possible to obtain the configuration I want (easily) with HDMI. Then I use xrandr to have 2 screens (laptop+monitor). Start spring without fullscreen, made the menu bar dissapear (xfce has a fullscreen option), and, at the end, use "/grabinput" in game so that mouse does not go to the laptop.