Thank you for your replies.
I have purchase workflow already which can be customized in pt.ini, e.g. I can add the following lines to allow for zero cost line items in POs:
[Customisations]
AllowZeroCostPOLines=1
Was hopeing I could do the same with PO. Pity.
VERY limited customizability really is the biggest downside of Accpac in my opinion, copared to other products.
Need the SDK for everything which is only available for Sage partners.