Thanks for sharing your baggage with us! (I love this extension of our arrivals lounge metaphor.)
Neither a camera nor a Twitter account are required -- you'll do fine without both. For the webinars it's much more useful to have a microphone, but you can even do without that, because we've always got text chat available. In particular, if your connection is slow, using a camera is likely to slow it even further, so may not improve matters.
As for Twitter, we include it as an optional add-on. In the past some people have used the course as an excuse to start an account and have a play around with it, others (like me and Marion) use it because they're already keen on it, and others have ignored it entirely, and posted all their thoughts to the discussion boards. All options are fine.
So the short answer is: don't worry too much about your baggage, it's not over-weight, and you won't be charged any supplements for it ;-)