Hey kelvin, don’t think its an issue with your setup here but an issue with the alpha network droplets actually. Just tried the url you linked and I get the same error as you with a manual proxy against the alpha network too. For some reason looks like about 20-25 of the 100 droplets running the alpha network had gone through a upgrade/power cycle.
http://blog.slabs.safenet/ for example partially loads up and can login to some accounts still so looks like the droplets restarting might have dropped data held too unfortunately in that interval if sync didnt catch up with the restart frequency. With a small number of vaults in the network, loosing few nodes end up having a big impact. Just my guess and need to confirm this is the cause for dropping data here though. Left the network untouched for now so the guys can have a look at the logs on Monday to see if it was maybe some other issue that caused the data loss. Just ran the invariant test on the network and it passes fine indicating network structure being ok. However for now would say that network certainly looks like its dropped data and you’re probably going to have better test results trying to use the TEST-11 network instead mentioned by @davidpbrown MaidSafe Dev Update - October 18, 2016 – TEST 11