I just got my Pineapple last night - when I tried to update from 2.4 to 2.7 over the web GUI, it went to a loading screen for a little over 1.5 hours. It finally refreshed with 172.16.42.1/pineapple/redirect.php, but continued to do that for the remainder of the evening. I finally pulled the plus this morning.
I'm guessing the best course of action is to flash it over a serial connection, but I've never used a serial - USB adapter before and am looking to order one today. My laptop only has a USB interface. All the adapters I see require a serial port on one side of the connection. Any advice here?