steps to reproduce:

1. create service model = ETSI SOL001 v2.5.1, category = ETSI NFV Network Service
2. choose 'topology.nodes.nfv.NS' as 'Substitution Node Type'
3. add some VFCs (do not use NS)
4. download CSAR
5. edit downloaded CSAR and add new property to 'topology.nodes.nfv.NS'
6. import edited CSAR - OK
7. check NS and see that added property not present in VFC - NOK