Hi dbornet,
I think you're a little confused....the function signatures on the V2-less functions are not the same as the v2 functions...so if you do not pass the right parameters correct behaviour will not happen. I'll give C# examples below, I write my reponses to a label.
MethodAPITableList
string XMLToReturn = ""; 
MethodAPI.Service _MethodAPI = new MethodAPI.Service(); 
lblMethodAPITableList.Text = _MethodAPI.MethodAPITableList(CompanyAccount, Login, Password, ref XMLToReturn); 
lblMethodAPITableListXMLToReturn).Text =XMLToReturn;
_MethodAPI.Dispose();
MethodAPITableListV2
MethodAPI.Service _MethodAPI = new MethodAPI.Service();
 lblMethodAPITableListV2.Text = _MethodAPI.MethodAPITableListV2(CompanyAccount, Login, Password, "");
_MethodAPI.Dispose();
 
Notice on the the v2-less function it's expecting xmlReturned passed in via reference as the 4th parameter, but v2 is expecting strSessionID passed in via value as the 4th parameter
MethodAPIFieldList
string XMLToReturn = ""; 
MethodAPI.Service _MethodAPI = new MethodAPI.Service();
lblMethodAPIFieldList.Text = _MethodAPI.MethodAPIFieldList(CompanyAccount, Login, Password, ref XMLToReturn, "Customer"); 
lblMethodAPIFieldXMLToReturn;.Text = XMLToReturn; 
_MethodAPI.Dispose();  
MethodAPIFieldListV2
MethodAPI.Service _MethodAPI = new MethodAPI.Service();
 lblMethodAPIFieldListV2.Text = _MethodAPI.MethodAPIFieldListV2(CompanyAccount, Login, Password, "", "Customer"); 
_MethodAPI.Dispose();
Same as with the table functions, the 4th parameter is different., so you cannot invoke them exactly the same way.
 
Dave