screen.getGlobalNode() fails - Member function not found...

Roku 4, 7.0 firmware.

If I copy the code example here: https://sdkdocs.roku.com/display/sdkdoc/ifRoSGScreen#ifRoSGScreen-getGlobalNode()

I get the failure below in the console. If I customize my code to use the getGlobalNode() I also get the same failure, what am I missing? Is this not available in my firmware version?

Current Function:
003:  sub showLandingA() 
004:    print "in showChannelSGScreen"
005:    screen = CreateObject("roSGScreen")
006:    m.port = CreateObject("roMessagePort")
007:    screen.setMessagePort(m.port)
008:*   m.global = screen.getGlobalNode()
009:    m.global.id = "GlobalNode"
010:    m.global.addFields( {red: &hff0000ff, green: &h00ff00ff, blue: &h0000ffff} )
011:    scene = screen.CreateScene("TrivialScene")
012:    screen.show()
Member function not found in BrightScript Component or interface. (runtime error &hf4) in pkg:/source/landing.brs(8)