MDX for Percent of Total for a subset of a Hierarchy

You should not use anymore the 'natural' hierarchy of a dimension (parent) to get the total but use a sum over the axis in your calculated members.

WITH MEMBER [Measures].[Percent] AS [Measures].[Result Count] / Sum( Axis(1), [Measures].[Result Count])  , FORMAT_STRING = 'percent'

That should get your 'visual' percentage.