Importing electronic invoices via Payables Open Interface Import program.

We are trying to implement electronic invoicing in a 12.2.4 eBS environment.  We are able to receive the electronic invoice information and load it into the interface tables.  However, when we run the Payables Open Interface Import program, it is failing.  Is there someone in the community who is at the eBS version who is creating invoices from electronic data recevied via OSN?  Also, how are the tax lines structured.  Are multiple tax jurisdications combined in a single tax line, or is there on invoice line for each tax jurisdiction?