I run my xim apex on pc with a dualshock 4 controller. However, when I switched to pc a few years ago I do remember having problems with the xim not working as well. I would plug the controller into the pc without the xim apex connected first so that the pc registers the device as a controller to be used on the system. You absolutely have to have a licensed ps4 or xbox controller in order for it to be recognize. Install steam and it will recognize your Ds4 or Xbox controller. Then you can set up your xim the exact same way that you would on console. Once you do that it should recognize the xim as a HID-compliant device as well as an xbox controller even though you are using a DS4 if you choose to. Make sure your mouse is set to 1000hz, you can set the xim to whatever you want. I used 1000hz on xim for a while before switching to 250hz. Then go into your game and set your in-game sensitivity to the recommended settings of your input translator. If you choose to use a DS4 you have to use the imput translator for playstation 4. Do not use the xbox translator because it doesn't feel right. Steam will recognize the Ds4 controller for what it is.
ps: DO NOT, AND I REPEAT! DO NOT DOWNLOAD ANY THIRD PARTY SOFTWARE LIKE SCP TOOL KIT OR DS4 WINDOWS!!! It's in all caps for a reason, your system will be riddled with malware and you will began to get the blue screen of death. DO NOT DO IT! I am speaking from experience. I don't care how bad you want the xim to work, if for some reason it doesn't don't be desperate and kill your computer. It's not an easy fix trust me. The malware will trick your device into thinking that it's healthy which will make it hard to discover the actual cause of the bsod.