Errors when trying to use an open SAP-connection

[Hermanito]

Hi all,
I'm still trying to get a SAP-connection working... so far I have this code (found somewhere else, slightly adapted to our situation). The logon-part works, so the first call in Main() is okay (I have changed connection details in the code pasted here). Then it halts on the next line (funcControl.Connection = Conn) with this error:
Run-time error '61704': Internal application error.
When I choose debug and immediately try to continue I get
Run-time error '-2147352568 (80020008)': Bad variant type

I've got no clue as to why this line gives these errors, I hope it's something silly I'm overlooking...
Does anyone have an idea what is going wrong here?

Dim LogonControl As SAPLogonCtrl.SAPLogonControl
Dim Conn As SAPLogonCtrl.Connection
Dim FuncControl As SAPFunctionsOCX.SAPFunctions
Dim TableFactoryCtrl As SAPTableFactoryCtrl.SAPTableFactory
Dim ZPP_BOM_DOWNL

Dim eQUERY_TAB
Dim TOPTIONS
Dim TDATA
Dim TFIELDS

Sub Main()
    Set LogonControl = CreateObject("SAP.LogonControl.1")
    Set FuncControl = CreateObject("SAP.Functions")
    Set TableFactoryCtrl = CreateObject("SAP.TableFactory.1")
    
    Call R3Logon
    FuncControl.Connection = Conn
    Call R3ZPP_BOM_DOWNL("T000")
    Conn.Logoff
End Sub

Sub R3Logon()
    Set Conn = LogonControl.NewConnection
    Conn.ApplicationServer = "10.0.1.1"
    Conn.System = "ZZZ"
    Conn.Client = "123"
    Conn.Language = "EN"
    Conn.User = "UserName"
    Conn.Password = "Password"
    Conn.RfcWithDialog = 0

    retcd = Conn.Logon(0, True)
    If retcd <> True Then
        MsgBox "Cannot log on!   - " & retcd
        Stop
    Else
        MsgBox "Logon OK"
    End If
End Sub

 

[Hermanito]

bump...

I hope someone can spot the error I'm making in this piece of code...
Is it how the variable is used? Is it a missing reference? I'm lost