RTC 5.0.2 iFix006

I would like to have a UI presentation that would help limit RTCusers enumerations based on a given parent selection hierarchy

Attribute1
     Attribute 2
        Attribute 3

in this example I can easily create a value set on Attribute1(source attribute) and Attribute2(dependent enumeration), and RTC allows me to create a value set similarly on Attribute 2 and 3 , yet i can seem to base a enumeration list for Attribute 3 based off of 1 and 2's selections

Yet it appears that I cannot effectively have a multi-level value value set or dependencies for more than 2 attributes ?
 
I have search the forums and havent see any similar inquiries, and wasnt sure if someone has already  posed this as an RFE

I see script based value sets maybe able to work, yet I am looking towards moving to eventually serving up these value sets externally as the parent\child combinations need to change weekly sometimes...