After updating our Commerce site with the latest packages (Update 96) I get the following error
"The route URL cannot start with a '/' or '~' character and it cannot contain a '?' character.Parameter name: routeUrl"
You can fix it by by removing the ~ from the rootPath for EPiServer in the protected modules node. This will fix Commerce throwing the error.
Problem is that when you use Find, the Find interface is not accessible from within the backend after making that change. And maybe other modules as well?
I posted this fix here, as it is most important that Commerce keeps working, but I think somewhere something in the routing should be fixed.