Script or import to take AP Invoices off of hold

I have a customer who wants to take AP invoices off of hold based on the condition that the AR invoices that go to that invoice have been paid. I ran into an issue with VI importing where I can't get it to let me take an invoice off of hold (This is for Sage 2013, PU2). My thought was to write a script where I could pass a file to the script and effectively take the AP invoices off of hold that way. I was wondering if anyone had done this and possibly had some sample code I could review. All of the scripting I've seen online to date relates to Sales Order and I haven't seen any good examples where a file is being passed in. Any information or pointers to resources to do this would be great.