Cursor jumps around when transitioning to second Windows computer

[Amablue]

I have two Windows 10 computers. One is a laptop and one is a desktop. On my desk at home I have three monitors. The two on the right are my desktop's monitors. On the left I have an older spare monitor, and when I have my laptop at my desk with me I'll plug it into that monitor so my laptop can have dual screens instead of just the one. So my setup is a follows: [Laptop] [Laptop secondary monitor] [Desktop monitor 1] [Desktop monitor 2]. The laptop is the client and the desktop is the server. My laptop's screen is 2560x1440. My secondary monitor is 1680x1050. My Desktop's monitors are both 1920x1080

When I use Synergy and the laptop has no secondary screen attached it seems to work fine, at least so far. When I have the second monitor attached though, it gets a little bit buggy. Here are the reproduction steps:

1) Start with the cursor on Desktop Monitor 1.

2) Move left to the Laptop secondary monitor. Everything is fine so far.

3) Continue moving left to the laptop's built in screen. As you move leftward across the screen, the cursor will jump back to the laptop's secondary monitor. This jump occurs when you cross approximately a quarter of the screen, and the position it jumps to is about a third of the way from the left of the laptop secondary monitor.

4) If you continue moving left and make your way to the laptop's built in monitor everything is fine now. It can move around without issue. 

5) Move the cursor back to the secondary monitor. As you cross vertical line where the cursor appeared when it jumped, it will jump again back to the laptop's monitor where it initially disappeared from

To more clearly illustrate what I'm describing, I drew a little picture in MS paint of what's going on. Imagine I move my mouse to the left until I hit the far left edge of the screen, then start moving right to get back where I started. I graphed the x position of the on screen cursor over time showing where the jumps occur.

 

[Snarf]

I have the same problem.  Did you ever get this sorted out?

[Snarf]

Ah, I see you did work it out and explained somewhere else: