If you go back your eBay Messages and open up the messages received from the seller, and the messages that you sent to the seller, each of them will have an option in the top right hand corner which says "Print", thus enabling you to print off the messages should you wish to do so. However, when viewing messages on the screen, the message that was sent prior to the one at the top of each message is displayed in grey, so it may not show up as well when you print it out. The only other way around this would be to print out every message that you sent to the seller, and every message that the seller sent to you, then put them all in order. You'd still be able to see the previous message displayed beneath each one, but by finding the previous message and printing it out so that that message shows as the most recent message at the top of the page it would then show you the text that appeared in grey when you printed off the reply to that message. Once you've printed off all of the e-mails manually scan them onto your computer or laptop and save them as a PDF. That way you'd have copies of all of the correspondence saved in PDF format.
With regards to the threat of court action, this may be nothing more than the seller letting off steam because he is feeling angry at having to refund the money from the sale. If the laptop really did get damaged in transit on its way back to him then the Royal Mail would have notified him that the item had indeed sustained damage during transit, in which case he would be able to provide this as evidence. If, on the other hand, he is just making it up then without any solid proof that the item was definitely damaged in transit his allegations wouldn't stand up in court. Therefore, unless the seller ends up sending you some kind of official confirmation that he is taking action against you in the civil court then I wouldn't even bother worrying about it.
Finally, in order to prevent the seller from being able to contact you via eBay, add his User ID to your Blocked Bidders List by clicking on this link https://offer.ebay.co.uk/ws/ebayISAPI.dll?bidderblocklogin. A big white box will appear on the screen - add the seller's User ID to that white box and then click on the Submit button beneath it. However, given that you've recently been in a transaction with this seller the blocks on the messages will take longer to kick in than they would have done had you never bought anything from this seller, although once they do kick in the seller will no longer be able to contact you via eBay Messages.
Should the seller become really persistent and take to sending you PMs via the eBay Community forums click on the message to open it, then click on the blue button that gives you the option to block messages from that person. If you do that then you'll receive no further PMs from that seller and he will more than likely give up harassing you when he keeps on receiving messages telling him that his e-mails couldn't be sent.
