Purchase order issues

I have an 3 issues with purchase orders that are required for my organisation to use this functionality within servicedesk plus, these are:

Ability to add a custom field, or the adding of a cost centre to log which cost centre who requested the item. I use PO name at present, but it is far from ideal. Is this possible.

Ability to add an attachment, such as a licence scan to satisfy FAST for licence compliance. Will this be available in the future?

When I create a new purchase order for a software title, I seem unable to add a new software title, Microsoft Autoroute for example. It appears that I can only add software titles that have been scanned. Is there a workaround for this?

Thanks

Jerry