You are correct. Version 3.80 must follow the pattern for naming properties as PLCAddress<propertyname>, where <propertyname> is the property the returned value will be put into. This is the corrected code:
'*****************************************
'* Property - Address in PLC to Link to
'*****************************************
Private m_PLCAddressSelect1 As String = ""
Public Property PLCAddressValueSelect1() As String
Get
Return m_PLCAddressSelect1
End Get
Set(ByVal value As String)
If m_PLCAddressSelect1 <> value Then
m_PLCAddressSelect1 = value
'* When address is changed, re-subscribe to new address
SubscribeToCommDriver()
End If
End Set
End Property
'*****************************************
'* Property - Address in PLC to Link to
'*****************************************
Private m_PLCAddressSelect2 As String = ""
Public Property PLCAddressValueSelect2() As String
Get
Return m_PLCAddressSelect2
End Get
Set(ByVal value As String)
If m_PLCAddressSelect2 <> value Then
m_PLCAddressSelect2 = value
'* When address is changed, re-subscribe to new address
SubscribeToCommDriver()
End If
End Set
End Property