axlCns functionality regarding dbid for named netclass

Hi

I've been trying to work with the axlCnsClassTable functionality but do not seem to be able to get it to work.

I create an empty netclass "OLE"

  arg2 = "OLE"
  nc_domains = '(spacing physical)
  ncls = axlNetClassCreate(arg2 nc_domains) 

Then I use the syntax from the axlCnsClassTableCreate (where the scset DP2ALL and pcset 50R already exists)

  props = '((spacing "DP2ALL") (physical "50R"))
  tbl = axlCnsClassTableCreate(ncls nil nil props)

but this will return nil.

I've also tried to get the dbid for the netclass named  "OLE" using axlSelectByName("NETCLASS" "OLE") and then use the axlCnsClassTableChange to set constraint sets for the netclass OLE

 but axlCnsClassTableChange will complain that the dbid is not a valid tableid.

My question is twofold

1. Is there no functionality to get the tableid for an empty netclass?

2. How can I make a constraint set reference on a netclass since axlCnsClassTableCreate does not seem to accept nil as the argument both for class2 and region? Alternatively, how can I use axlCnsClassTableChange to set a constraint reference on an empty netclass

Thanks in advance.

Best regards

Ole