Hi Jeff,
You should be able to simply list two copytable functions after another in the script to execute. I find it useful copying and pasting into notepad or any other text editor, as the text character constraints inside the button action can be challenging when editing longer script strings.
Here is an example of two copy table functions that are executed as part of a script in order to bring data into two different datasets (IFRS_CM_DataSet1 and IFRS_CM_DataSet2) in the current project, this assumes you have knowledge of Apptio data paths and how copytable functions are constructed.
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CopyTable("<%=DomainName()%>:<%=ProjectName()%>/Data/<%=CurrentDate("MMMM:yyyy")%>/APPTIO_IFRS1_CMD/.RawTable/","<%=DomainName()%>:<%=ProjectName()%>","IFRS_CM_DataSet1","January:2014")
CopyTable("<%=DomainName()%>:<%=ProjectName()%>/Data/<%=CurrentDate("MMMM:yyyy")%>/APPTIO_IFRS1_FYD/.RawTable/","<%=DomainName()%>:<%=ProjectName()%>","IFRS_CM_DataSet2","January:2014")
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Hope this helps!
Seth