Purchasing feature

I have been using SD+ for a 2 months now and on the whole its pretty much what we want and the update list and support is great.

I have a request regarding the purchasing feature. Would it be possible to part-recieve items, not all items purchased on one PO number arrive to us on the same day.

Also from a invoice checking point of view we would like the purchase order not to be closed after items have been recieved but only when suppliers invoices are sent.

For example a feature which will allow us to invoice check agaist our PO and then close the purchase order. The problem arises when the IT manager needs to make payments for outstanding supplier invoices but PO's are closed once the goods arrive and we receive them.

Thanks