The invoicing is now ready for "pay when project is finished" as well as "pay when milestone is finished" as milestones are subprojects.
You can "simulate" pay as you go by having one project for a customer per month and changing the cost sheet at the end of the months, looking (manually) which projects the client has spend hours on. Alternatively you could run a manual query for the logger package. Writing this should take a couple of hours, but is fairly straigtforward (you first lookup all project_item_ids of the customer you want to send an invoice to. Then you loop over each project_id and add an entry into the invoice_items table with the amount of hours spend (looking up and aggregate over the month in logger with the project_id). Probably you have to make some minor calculations for the total amount etc to insert the invoice into the invoices table.
Hope this helps and I'd be delighted if you could get this working.
