SAP CRM Business Partner - Middleware debug

Had a problem with debugging the BP middleware from CRM to ECC and found the following answer in SDN:

• Put a break point in FM SMW3_MFLOW_UPDATETASKBDOC. 
• Create a BP and before save type /h to activate debug, mark update debugging option. 
• When stops in FM SMW3_MFLOW_UPDATETASKBDOC you must be sure to set header-dbgmode = 'X' this will make the bdoc stay stopped in SMW01. 
• Go to SMW01 and type /h and process the bdoc. Put a break in FM CRM_UPLOAD_AFTER_MAP_HANDLER and be sure to change LV_SYNCHRON = 'X' this will allow you to connect in ECC. 
• Put a break-point in the "CALL TRANSACTION" command. Change the mode of call transaction and you be able to debug XD* update.

NOTE: to check/resubmit BP from CRM to ECC, use txn: CRMM_BUPA_MAP