If you need to develop the application independently of the Gui components, an alternative approach would be to create a namespace, read the file into it, and #.CPro.Make the MDI child in the right namespace. This avoids the need to localise any data on the MDI children and makes it very easy for you to )CS to the right space to check out your data. Here is an alternative version of the main form which makes two MDI children in the existing sub-namespaces ns1 and ns2:

ÚÎÎÂÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÂÎÎÌ
ÛCRÛÛtop„’’                                  Û{}Û
ÃÎÎÏÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÏÎÎÝ
ÛPCÛÛ’Make #.Class.MakeBar dbx.mdibarns      Û{}Û
ÃÎÎÏÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÏÎÎÝ
ÛPCÛÛŒCS ‘ns1’ ª ’Make ##.dbx.nsch ª ŒCS ‘##’Û{}Û
ÃÎÎÏÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÏÎÎÝ
ÛPCÛÛŒCS ‘ns2’ ª ’Make ##.dbx.nsch ª ŒCS ‘##’Û{}Û
ÀÎÎÁÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÁÎÎÙ

... of course in a real system you would make these namespaces dynamically as part of your ‘File, Open’ processing. The tool buttons use a simple CPro utility to check the namespace of the top form and switch into it:

      Disp œdbx.mdibarns[6; 5]

ÚÎÎÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÌ
ÛBehaviour  ÛÚÎÎÎÎÎÎÂÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÂÎÎÌÛ
Û           ÛÛSelectÛ      Ûctx„’GetContext top               Û{}ÛÛ
Û           ÛÃÎÎÎÎÎÎÏÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÏÎÎÝÛ
Û           ÛÛSelectÛ0<½ctxÛŒCS ctx ª txt„²txt ª ’Notify ‘txt’Û{}ÛÛ
Û           ÛÀÎÎÎÎÎÎÁÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÁÎÎÙÛ
ÃÎÎÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛAcceleratorÛCtrl+f                                               Û
ÃÎÎÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛActive     ÛÚÎÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÌ                                  Û
Û           ÛÛExpressionÛ0<½topÛ                                  Û
Û           ÛÃÎÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÝ                                  Û
Û           ÛÛDependenceÛ{top} Û                                  Û
Û           ÛÀÎÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÙ                                  Û
ÀÎÎÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÙ

Exactly the same approach works with the floating tool palette, but here you might consider switching the entire palette into the appropriate namespace, as it is likely that all the tools will operate on the existing data:

     Disp œ(œdbx.mdipal[1;5])[2;2]

ÚÎÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÌ
ÛExpressionÛ’GetContext #.Tutor.topÛ
ÃÎÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛDependenceÛ{#.Tutor.top}          Û
ÀÎÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÙ

The only really important point here is that you must fully qualify the variable names, as the palette itself will move around as top changes. Now the actions on the tools can be made really simple:

     Disp œdbx.mdipal[2;5]

ÚÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÌ
ÛBehaviourÛÚÎÎÎÎÎÎÂÂÎÎÎÎÎÎÎÎÂÎÎÎÎÎÌ        Û
Û         ÛÛSelectÛÛtxt„²txtÛ{txt}Û        Û
Û         ÛÀÎÎÎÎÎÎÁÁÎÎÎÎÎÎÎÎÁÎÎÎÎÎÙ        Û
ÃÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛBitmap   ÛÚÎÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÌÛ
Û         ÛÛExpressionÛ12 12½0 7 7 0 0 0 0ÛÛ
Û         ÛÀÎÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÙÛ
ÃÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛDrawn    ÛOffice97                        Û
ÃÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ
ÛActive   ÛÚÎÎÎÎÎÎÎÎÎÎÂÎÎÎÎÎÎÎÎÎÎÎÎÎÎÌ     Û
Û         ÛÛExpressionÛ0<½#.Tutor.topÛ     Û
Û         ÛÃÎÎÎÎÎÎÎÎÎÎÏÎÎÎÎÎÎÎÎÎÎÎÎÎÎÝ     Û
Û         ÛÛDependenceÛ{#.Tutor.top} Û     Û
Û         ÛÀÎÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÙ     Û
ÀÎÎÎÎÎÎÎÎÎÁÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÙ

You might like to experiment with the example code in the Tutor namespace, and make some nice bitmaps to populate a suitably Office97-style floating toolbar.