>>customer1.GetByName ("cust name")
>>?customer1.CustomerAddress()
>>set the fields required and then
>>customer1.Add()


You can achieve something very similair directly;

loQbsession=CREATEOBJECT('QBFC5.QBSessionManager')
loQBRequest= loQbsession.CreateMsgSetRequest("UK",<XMLVersion>,<XMLMinorVersion>)  && set for your country/version

loCustomer=loQBRequest.AppendCustomerAddRq()

WITH loCustomer
  .CompanyName.SetValue("<Customer Name>")
  .BillAddress.addr1.SetValue("<Address Line1>")
  .BillAddress.addr2.SetValue("<Address Line2>")
   *! etc etc.
ENDWITH
  
loResponse = loQBSession.DoRequests(loQBRequest)    && Save Details

*! or to modify an existing
loCustomer = loQBRequest.AppendCustomerModRq()

FYI: from my experience speed is VERY dependant on network, local queries on machine with QuickBooks installed have a reasonable performance, when accessed across network performance deteriorates significantly (another reason for a server based approach?)

Gary.