Hi, I'm very sorry for those controls issues. Usually, it is caused by a gamepad, a joystick or some other device acting as one. You can try to unplug those. One player had an issue with an old 3D mouse driver, that he needed to uninstall to make it works. Another one unistalled VJoy, which is a virtual controller software.
To reset the custom inputs you may have entered, you have to delete them in the registery, To do it easily, you can use the following command line: reg delete "HKCU\Software\NuSan\Fragments of Euclid" /f
If you don't know how to enter a command line, you can also download the following file and execute it :
I hope you will be able to play. I should make a new version with an option to disable gamepad controls, as you are not the first to have issues with it.