Hello, I'm affraid it's not possible to do it by using the verb "AddNodeToNCM" since the only acceptable argument is "CoreNodeId".
Setting of the credentials is possible via Update/Set operation. Honestly I'm not very familiar with the language you use, but to demonstrate the principle, please see bellow the part of the code written in PowerShell:
$Target="10.140.2.180"
$swis = Connect-Swis -host $Target -UserName admin -Password "123" -V2
[System.Int32]$NodeIdToAddToNCM = 11 ##Specify the nodeId you need to add to NCM
Invoke-SwisVerb $swis Cirrus.Nodes AddNodeToNcm($NodeIdToAddToNCM) ## Add Node to NCM
[System.String] $Uri = Get-SwisData $swis ("SELECT Uri FROM Cirrus.Nodes WHERE CoreNodeID = " + $NodeIdToAddToNCM) ##Get the Uri of the updated object
Set-SwisObject $swis $Uri @{UserName='user1'; Password='bla'} ##Specify the property bag to update and perform the Update action
I hope this helps at least a bit.
Honza
