My knowledge of NexGen is very limited. (I know it's called NexGen without the T letter and it's a pricey solution widely popular in US OTA Radio stations)
Information about it on the internet is scarce as people usually pay RCS for support and don't rely on a community of volunteers.
This is the only info I could find on the Export feature:https://mediarealm.com.au/articles/expo ... cs-nexgen/
I'm not sure about the options available here as I've seen screenshots of different versions of NexGen apparently.
You should configure the export to send TCP-IP in whatever format you like. XML seems to be a reasonable choice as you can adapt one of the example scripts shipping with SAM Cast to process the more detailed NexGen output that way. (It won't work out of the box as the NexGen Output definitely is more verbose than what the example script expects)
In SAM Cast you need the TCP Event Adaptor and a custom script to extract the parts of the XML you need for metadata. There is an example XML parser included, but that one expects a very simple XML format and will most likely fail to understand the more complex and verbose XML document sent by NexGen. (vb.xml_parser.txt)
Make sure to set up port forwarding if the NexGen and SAM Cast machines are not on the same network and at least allow the port specified in SAM Cast for incoming connections on a possibly activated personal firewall (windows firewall is most likely present if you didn't install one alongside your antivirus)
If you need help with building the parser script, feel free to ask questions here.
To get the parser script made for you without you having to do the programming yourself, please send me a message and we can agree on a price. (Depends on how much info I get, if I should do a remote session and set things up for you, how complex the NexGen XML structure is and how much/what info you want to extract from there.)