Understand that Dashboard authoring is a custom development task, and my ability to help is going to be limited, but you can search this forum to find some good resources.
The Session Relevance I’m using to find fixlets for my baselines is
(it as html) of ("<BaselineComponent Name=%22" & (name of it as html) as string & "%22 IncludeInRelevance=%22true%22 SourceSiteURL=%22" &
url of site of it as string & "%22 SourceID=%22" & id of it as string & "%22 " & (if exists default action of it then " ActionName=%22" & content id of default action of it as string & "%22 " else "")& ">%0d%0a<ActionScript MIMEType=%22application/x-Fixlet-Windows-Shell%22><![CDATA[//add actionscript here" & "]]" as html as string & "></ActionScript>%0d%0a<SuccessCriteria Option=%22OriginalRelevance%22></SuccessCriteria>%0d%0a<Relevance><![CDATA[true" & "]]" as html as string & "></Relevance>%0d%0a</BaselineComponent>"
) of elements of set of items 0 of
(item 0 of item 0 of it, name of item 0 of items 0 of it, item 1 of item 0 of it)
whose (true) of
((it, unique values of preceding texts of firsts " " of operating systems of applicable computers of it as lowercase) of
(fixlets of bes sites whose (name of it is contained by "Enterprise Security|Updates for Windows Applications")) whose
(fixlet flag of it AND applicable computer count of it > 0 AND (exists (applicable computers of it) whose (now - last report time of it < (60 * day)))AND (if not exists display category of it then true else display category of it is not contained by set of ("Audit"; "Bug Fix"; "Configuration"; "Definition Update"; "Hotfix"; "Microsoft Unsupported"; "Registry Setting"; "Setting"; "Uninstall"; "Update"; "Updates"; "updates")) AND name of it as lowercase does not contain "superseded" and exists default action of it),
set of (it) of (fixlets whose ((category of it contains "Patch") and baseline flag of it) of
(bes custom sites whose (name of it = "MY_PATCH_SITE")))) whose
(not exists (it, elements of item 1 of it) whose
(item 0 of item 0 of item 0 of it is contained by set of source fixlets of components of component groups of item 1 of it and
(category of item 1 of it as lowercase contains "win_all" or category of item 1 of it as lowercase contains item 1 of item 0 of item 0 of it as lowercase)))
This grabs the XML content for embedding fixlets into a new baseline; I have functions before and after this piece that create the rest of the baseline wrapper into which this result is embedded, then I use the ImportXMLToSite() function to create the baseline.