Maybe if you try this solution with replacing the default “3dxrhino.rhp” plug-in with the one from Rhino 6.3, it will work on you Rhino? Keep in mind that every time you update Rhino 7 with a new Service release, it will replace the “3dxrhino.rhp” plug-in and so if you wish to continue using the older Rhino 6.3 “3dxrhino.rhp” plug-in you will have to replace the default one manually once again. Since I use a discontinued SpacePilot device (intentionally discontinued by “3Dconnexion” so that they could force you buy their new devices) which is no longer supported by the Rhino 7’s default “3dxrhino.rhp” plug-in. That gives me the chance to use my SpacePilot in Rhino 7. 
Fun fact: The “3dxrhino.rhp” plug-in used in Rhino 6.3 was actually a Rhino 5 plug-in, so basically now I use Rhino 7 with a Rhino 5 “3dxrhino.rhp” plug-in. 
This way, the LCD screen of my SpacePilot recognizes Rhino 7 as Rhino 5 instead, so it works as a time machine.