"should I be filing a complaint with Paypal at this stage or waiting to see what happens"
Palicomp seem to want to resolve any issues that you are experiencing, either by telephone support or by returns method, so its only fair to give them a chance to put things right. But having said that, PayPal have a cut-off time in resolving complaints, so it might be advisable to contact PayPal and ask their views, or read up Ebay/PayPals terms and conditions regarding Resolution.
If you paid by credit card through PayPal, then you might need to consider the way your credit card company will deal with this matter at a later time(if problems are not resolved), possibly under section 75 of the Consumer Credit Act, because the transaction as gone through PayPal's procedures.
You should also consider that you have extra rights under the Distance Selling Regulations (DSR), if you made the complaints within the 7 day period on receipt of the item, and hopefully have kept records of communications.