After the upgrade (from 1.3.7 to 1.5.0) I am no longer able to edit (or even view completely) orders/invoices. Clicking on the edit will bring up the order screen, list the customer/adress, shipping address, billing address, tel, email, ip, invoice #, date purchased, payment method (and details of the payment), referral - and then nothing else. No product purchased or totals, no special instructions, no update process fields. It's just blank from that point on. Same thing when viewing the invoice - it doesn't list anything after referral.

Any thoughts on what might be happening here or where I should look to see if there is some errant/bad code running around?