RESThopper not working after update (7.0.20126.10465)

After updating Rhino WIP to version 7.0.20126.10465 RESThopper is not working anymore.
I am getting this error on an example that previously worked:

{‘statusCode’: 500, ‘message’: ‘Something went horribly, horribly wrong while servicing your request.’, ‘details’: ‘Nancy.RequestExecutionException: Oh noes! —> System.ArgumentOutOfRangeException: Der Index lag außerhalb des Bereichs. Er darf nicht negativ und kleiner als die Sammlung sein.\r\nParametername: index\r\n bei System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)\r\n bei compute.geometry.ResthopperEndpointsModule.Grasshopper(NancyContext ctx) in C:\projects\compute-rhino3d\src\compute.geometry\ResthopperEndpoints.cs:Zeile 474.\r\n bei Nancy.Routing.Route.<>c__DisplayClass4.b__3(Object parameters, CancellationToken context)\r\n — Ende der internen Ausnahmestapelüberwachung —\r\n bei Nancy.NancyEngine.InvokeOnErrorHook(NancyContext context, ErrorPipeline pipeline, Exception ex)’}

Is it possible to downgrade Rhino 6 WIP?

it is not a problem of the version

Please supply more information, like which call are you making to compute, etc.