I bought recently phantasmagoria in humble bundle and it's packed for steam windows. As I'm using linux and the game is run through dosbox I wanted to run it under my daily operating system and found some problems:
when I move the mouse the cursor position resets to the middle of screen, I recorded a video. https://youtu.be/80f9SOQgPgE
I tried to disable the joystick from auto to none in the config file, because it looked to me somehow like a joystick behaviour but it didn't help.
I've changed the mouse driver to NONE because the original didn't work - now I don't remember what was there originally, but it didn't change anything. Now I also tried with mouseDrv = STDMOUSE but the same results.
edit. now lookin closer the driver files should be in the same directory as the game - my mouseDrv was something with 3 letters and I don't have any STDMOUSE either so this might be the case. The files I have:
There is no mouse driver. The default for the cfg is "NONE". I cannot replicate your issue. I am on Windows 7, but I doubt that that would make a difference. Try "mouseDrv = STD" and changing your autolock setting.