I'm using V2 software and the issue I'm having as that when I pull the plunger it starts off really slow (ie 10mm of real plunger pull moves the virtual plunger about 2mm) and then 'speeds up' to the point where after about 30mm then it gets closer to 10mm real to 10mm virtual. Is this just something to avoid a bit of jitter when the plunger is at rest? Or is this because VPX is setup for a key press plunger so it is hard coded to accelerate up to speed?
I can think of two possibilities:
1. You're using an audio-taper potentiometer. You didn't say what kind of sensor you're using, but if it's a pot, it needs to be a "linear taper" type. The behavior you describe would occur if you use an "audio taper" type, which has a logarithmic resistance curve, which would produce the kind of response curve you're seeing with varying speed across the pull range. If you're using an optical sensor, this obviously isn't the issue.
2. You might have run the Windows joystick calibration. The Windows calibration is bad for plungers; don't use it. If you might have accidentally run it in the past, you can delete the calibration as follows:
Bring up the Start menu search box or Press Windows+S
Type "set up usb game controllers" into the box
Click on "Set up USB game controllers" in the result list
Double-click "Pinscape Controller" in the list
Click on the "Settings" tab
Click "Reset to default"
Other issue is that I find that half a plunge pull on the real and already the virtual is beyond the little window... shouldn't a full pull still show the tip in the virtual?
I'm not sure what you mean - are you talking about VP or the Pinscape Config Tool?
If you're talking about VP, then what "should" happen is entirely up to the particular table you're playing. Different tables have different plunger animations. Some of these animations can show the plunger pulled back all the way, others can't.
If you're talking about the Pinscape Config Tool, you might just need to run its calibration. (Note: this is completely different from the Windows joystick calibration that I was talking about above.) Run the config tool and click on the Plunger icon. Click the Calibrate button and follow the on-screen instructions.