4 things you need to correct in your form..
1) Page1 subform needs tobe set to Flowed.
2) Then the Subform1's binding tab will be active. You need to check the checkbox for "Repeat Subform for each data item".
3) In the add button for Subform1 you missed "instanceManager" in the code..
Subform1.instanceManager.addInstance(1);
4) Similarly in the Delete button
Subform1.instanceManager.removeInstance(this.parent.index);
Thanks
Srini