How can you filter a fixlet based relevance query by computer groups?

I have several relevance queries that are fixlet based (where " of bes fixlets" is at the end of the query) and I need to set up a system to filter their results by a computer group that will be in put by the user.

I’ve tried doing it like this…

(names of it, source severity of it)
of
item 1
of
(it, bes fixlets whose (exists results of it))
whose (id of computer of result of item 1 of it = item 0 of it)
of
(unique values of ids of members of bes computer groups)

but it took much longer to return results than the original query, and when I compared the results it returned with those of the original query I discovered that it was also returning different data (I wasn’t filtering on a particular computer group so the data should have been the same as the original query)

How can I get this to be both faster, and return the correct data?

Original query for comparison:

(names of it, source severity of it)
of
bes fixlets whose (exists results of it)

Not exactly clear on what you are looking for, but maybe something like this will return the fixlet id, name, category, source severity, applicable computer count of a particular computer group within a specified site:

(
id of it , name of it , category of it , source severity of it , number of applicable computers of it
)

of bes fixlets 
whose
(
	applicable computer count of it > 0 
AND
	display name of site of it = "Patches for Windows" AND exists members of bes computer groups whose (name of it="Patching Group 1")
)