You are right. That wasn't the right approach.
*Dont know if it makes any difference but there is no Direct_Output or Writeln commands in the bp.

Following the "Channel Command Component" example within the help, this is what I implemented:
Code:
//Create Logfile and channel
Move (Seq_New_Channel()) to iOutChan
Direct_Output channel iOutChan sOutput
Writeln channel iOutChan ("Start Update procedure: "+String(dtCurrent))
Get CreateAttachment of oAttachments sDownloadFilePath hTable hColumn iEmployerIdno (iContrId<>0) hTable sEmployerName "" (&iAttachIdno) to bSuccess
Writeln channel iOutChan (String(CurrentDateTime())*"Attachment record created: iAttachIdno:"*String(iAttachIdno)*"|"*sDocumentId*"|"*sDownloadFilePath)
Close_Output channel iOutChan
Send Seq_Release_Channel iOutChan