Here are some other articles here on steemit about these recent edits to the Bitshares Web UI:
https://steemit.com/bitshares/@docmastery/bitshares-newest-web-ui-released-v171205
https://steemit.com/bitshares/@money-dreamer/bitshares-gui-update
https://steemit.com/bitshares/@billbutler/bitshares-gui-release-v2-0171205
I think the upgrades are great and it makes using the site a much more pleasant experience.
I think the loading of the open orders and activity takes too long and hangs the web browser while loading. Possibly, it should only load the visible elements if it is not doing that already. I believe it loads a large amount of data into the browser cache on page load.
I don't have any "hangs". You may need to stop using your VPN since the BTS wallet uses sockets. Also, do you have a large number of followed accounts? This can also cause slowness.
I have a huge number of open orders. My browser freezes up when I click the Open Orders tab. I'm not going through a VPN and my internet should handle this without any problems.
It looks like the Activity tab has the arrow at the bottom to load more orders and the Open Orders tab loads all items by default.