I just mention that to put an order thru business functions is easier than putting an invoice and i have concrete examples, but for now I will concentrate on how you update the Z1 tables throu XML:
On every PC on which the fat client is installed you will find a directory named :\b7\system\bin32 In this directory you should find a dll named XMLTransactions.dll. In this file there is a function which we are going to use. Declare the following in your wrapper class init method :

DECLARE STRING _jdeRetrieveTransactionInfo@8 IN d:\b7\system\bin32\XMLTransactions.dll AS jdeXMLRequestTransInfo;
STRING XML, ;
INTEGER size

You can then pass your transaction as an XML via the former function. I use the following function, the property THIS.xmlJdeFunction, contains the xml string, i also log everything into the table jxmltempl ...

***********************************
FUNCTION JdeRunTrans
***********************************

LOCAL cJdeXml, lcJdeXmlResponse
*
cJdeXml = THIS.xmlJdeFunction
lcJdeXmlResponse = jdeXMLRequestTransInfo( cJDEXML, 0 )
*

IF !USED([JXMLTEMPL])
USE D:\ERPLEGACY\DATA\JXMLT.DBF IN 0 ALIAS JXMLTEMPL
ENDIF
*
LOCATE FOR ALLTRIM(JXMLTEMPL.JFNAME) == ALLTRIM(THIS.FunctionName)
IF !FOUND([JXMLTEMPL])
APPEND BLANK
REPLACE JFNAME WITH THIS.FunctionName
ENDIF
REPLACE JXMLTEMPL.XMLRESP WITH lcJdeXmlResponse
REPLACE JXMLTEMPL.XMLDOC WITH cJDEXML


ENDFUNC

For an example of what the xml doc should contain for the purchace order pls send me your personal address, because the xml doc is big

Dimitris