Use Summarize (or many other options) to get the unique values from column into a list and then use that to initialize your check box
Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Big Class.jmp");
Summarize(dt, user_options = By(:name));
nw = New Window("", << modal, << return result,
V List Box(
cb = Check Box(user_options),
Lineup Box(N Col(2),
Button Box("OK"),
Button Box("Cancel")
)
)
);
If(nw["Button"] != 1 | N Items(nw["cb"]) != 2,
stop();
);
show(user_options[nw["cb"]]);
-Jarmo