Disappearing Ethereum Transactions with the Aragon ICO

While trying to get in on the @aragonproject ICO today, I noticed the first transaction I submitted was taking longer than usual so I did a quick screen capture. A few minutes later the transaction stated “Unable to locate transaction entry” so I grabbed a screenshot of that as well. (see below) Since I only put enough Ether in my MetaMask wallet to cover the transaction plus a few extra Ether as a buffer for fees, etc. I figured I would just resubmit the transaction. I had the same thing happen two more times. On the fourth try the transaction actually went through. From what I have seen on Twitter so far, it seems like some other people weren’t as lucky.

Can anyone explain why this happened?

Is this just a limit of the Ethereum network ahead of the planned scaling upgrades?

Would love to get more info. In any case, huge congrats to the Aragon team on the second biggest ICO in history!