Wow that site is super fun :) As far as the sequencer, head over to the save menu. If you 'share' your sequence it actually generates a link you can save. (It's not storing the data in the link as the full sequence data is too long at once for a url string.)
Another option is to use base-64 or XML (or even JSON) to store the data in a longish text string that’s still short enough to share online. For example, he’s a really nice ambient “bloom” reverb I use with Valhalla Supermassive (after downloading this free plugin, one can copy the following code then select “paste from clipboard” in Supermassive to load this reverb):
Sigh. Ever read an early proposal and think "wow, that's such a bad idea - good thing no one will pick up that"? Very not safe - a young naive me thought that reading early CGI, with its short urls passed on command-line, rather than longer urls on stdin. But people lycosed, and found a page, and were guided by it, and it spread, and... became assumed. Oh well.
Here in the future, with IE gone, IIRC browsers permit 80k, bottlenecked on Safari. Base-64 drops thats towards 60k. Of compressed data. Bzip can do a lot, even with JSON. Especially if you help it out.
There's some robustness cost, with unhappy security gateways and such, but for apps where featureful trumps reliable, we're no longer quite so crippled. Yay.
