In this video I give the Surface RT a little bit of a push and load up 10-15 applications all at the same time. I also investigate how the tablet manages all these applications in terms of displaying them to the user.
Great video. I think that one lag you had going back to the screen was the previous app cache working. That also explains that one app closing a little slowly. This tells me that a restart is called for every now and then as well which would be quicker closing all those apps. Just sayin.
I haven't had much luck editing the whitelist either, but, sometimes the flash video on a website is actually hosted on another website, which you would have to determine by checking the settings for the flash video on a computer/device that can actually play the video.
If it's hosted on another website, you also have to enter that website in the whitelist file. So, you would have 2 entries: "gorillavid.in" and the other website.
A quick check of a video on the site lists another site, "images.gorillavid.in", under settings. Try adding that to the whitelist file as well, and see if it will work.
In this video I very briefly revisit a couple of gripes about applications from previous videos to say that things are improving. The first generation apps are starting to find their feet, but there is still a long way to go before parity with other tablet operating systems.