how to set"alt CombinedFragment" at staruml

Hi,
I had just found the steps as following.

1.create a sequence diagram like the following.

2.add a CombinedFragment1 into diagram like the following.

3.change the "seq CombinedFragment1 " to "alt CombinedFragment1 "

4.select the "Interaction Operand"

5.left-click at the "atl CombinedFragment1 ",you will found the one "InteractionOperand1" added into the "alt CombinedFragment1 ".

6.add the 2nd "InteractionOperand", same with step 4,step5, there will a parting line like the following.

7.set the InteractionOperand's Guard data,my is "isInit",you will found it at the alt frame.

8.add the 2nd Guard data,same with the step7.

9.move the diagram to the proper location.like the following.

while,I still have something unknown, for example, how to make the frame located at the top front and add a relationship with the "B method".
Wish it helpful to u.