Here is info that I've found/received from RateLinx:
The following was sent by Brad in the Issue Tracker regarding the WS call to use the PrintManifestEx call:
"To get the usps scan form like the shiplinx front end does, one can access the PrintManifestEx web method. Additional information can be found on the shipsource server at http://shiplinx.shipsource.com/ratelinxwebservice/ratelinx.asmx?op=PrintManifestEx
One example we got a response for with client data had the following passed to PrintManifestEx. *Fields not shown in the below list were passed with empty strings.
clientid = "SKYGEEK"
username = "administrator"
locationID = "2864"
carrierID = "USPS"
manifestID = "28640679_2864_END"
fmtType = "PortableDocFormat
The example returned xml from the above is attached to this issue now. We only get PNG scan forms back from Endicia so the fmtType parameter value sent does not really matter as long as it is one of the valid values."
***
They need to use the PrintManifestEX call and pass in: clientid, username, password (which isn't listed), locationID, carrierID (USPS), manifestID (from the CloseEx call), and fmtType (PortableDocFormat).