Sap Cua configuration issue [pertaining to logical systems]

Hi all ,

I am performing a CUA configuration.

Following are the systems :

• System ABC with client 123 (central)
• System PQR with client 456 (child)
• System XYZ with client 789 (child)    

I have logged into all the 3 systems individually(with user SAP*) and created an admin user [CUA_ADM] [ SAP_ALL and SAP_NEW]

Next we come to the specification of the logical systems using BD54 or SALE

ABCCLNT123

PQRCLNT456

XYZCLNT789

As per my understanding this is how the process flow should work:

1.ABC

I login to the ABC system (client 123) using the CUA_ADM user and specify the logical systems

ABCCLNT123

PQRCLNT456

XYZCLNT789

All three i.e., 1 central + 2 child

2.PQR

I login to the PQR system (client 456) using the CUA_ADM user and specify the logical systems

ABCCLNT123

PQRCLNT456

XYZCLNT789

All three i.e., 1 central + 2 child

3.XYZ

I login to the XYZ system (client 789) using the CUA_ADM user and specify the logical systems

ABCCLNT123

PQRCLNT456

XYZCLNT789

All three i.e., 1 central + 2 child

Is the approach/logic correct ??

That is do i have to specify the logical systems of both the central and 2 child systems in each of the three given systems ?

Kindly help