Reg. Modifying Group population using registry key

Hi All,

We have following requirement and I request community input on how to achieve this.. 1. There is existing custom sealed MP, which has a discovery defined based on registry key.  (eg. supported SQL servers based on registry entry 'abc') 1. We need to discover additional set of servers based on separate  registry key value ('xyz')
2. Populate these additional servers in the same group as above (group-1)

My approach
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1. create a new discovery rule based on new registry key and seal it and import in SCOM   (I have done this step)
2. export the existing sealed MP (from scenario -1) ,  Edit the xml  and in Group population - dynamic member section add additional formula to include the new registry key.

Issue:
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I got stuck at step 2 in my above approach. I could not find the dynamic member section where I can add the new registry information. Is it stored in DB somewhere?

Suggestion welcome
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If my approach is wrong, can anyone please advice me on how to implement the new requirement?

Any help would be greatly appreciated.


Regards,
Sri