Ah, I didn’t see the settings in the Plugins section. I found the IDs, and mapped the device, but still gettting the same error. Reading up on the error from MSDN, it looks like the HID isn’t getting parsed correctly (it looks like what is being described here: Troubleshooting HID Reports - Windows drivers | Microsoft Docs). I’ve created the bug report, as suggested: https://answers.unrealengine.com/questions/559637/rawinput-plugin-hid-report-not-being-parsed-correc.html
<edit> I did reach out to 3DConnexion, and their response is that their HID is built to the USB HID spec rev. 1.11, so there’s nothing they can really do on their end, which, assuming they’re right and the issue isn’t that they messed up and released a non-standard HID, then they’re right. The fact that the USBlyzer is able to parse the HID correctly, as seen in the PDF attached to the bug report, supports their claim.</edit>