The SEM platform can build highly customizable path diagrams but it won't allow you to include content inside the nodes beyond a label (which comes from a column name in the data table). Indeed, because the diagram is application specific, the nodes aren't designed to fit a lot of content.
You can try running the JSL below to see it for yourself. As a side note, you can specify the diagram interactively using From/To lists if you just run the first two lines of the script. You'll be able to connect nodes with double-headed arrows and can use the context menu in the diagram to find the "Customize Diagram..." menu.
// Create data for use in the structural equation models platform
mat = J(50, 7, Random Normal());
As Table(mat, << Column Names({"A", "B", "C1", "C2", "C3", "C4", "D"})) << Set Name("Flow Chart");
// Launch SEM and specify diagram
obj = Structural Equation Models(Model Variables(1::7));
obj << Model Specification(
Regressions( // lists follow "from-to" convention
{:A,{:B}},
{:B, {:C1, :C2, :C3, :C4}},
{:C1, {:B}},
{:C2, {:B}},
{:C3, {:B}},
{:C4, {:D}},
{:D, {:C4, :A}}
),
Path Diagram Properties(
Manifest Shape({Width(70), Height(40)}),
Layout("Top to Bottom")
)
);
You can get a quick overview of what the SEM platform is meant to do here:
https://www.jmp.com/en/statistics-knowledge-portal/structural-equation-modeling
HTH,
~Laura
Laura C-S