Please note that safeSpace is in live Beta testing until the end of 2018. We are happy to offer you a 50% discount until then.
4-1) Yes, unless they have blocked it. Whether you should or not depends on your workplace. We would hope people are actively encouraged to use safeSpace at work, in good faith, as a means of encouraging dialog and exchanging of ideas. Many of us are stuck in stale and entrenched positions... it is in everybody's interest to find a way forward. If in doubt, we suggest you come to an agreement in advance, so that the privacy is respected. Here's a sample agreement you are welcome to use. We strongly siggest you negotiate and modify this to suit your own national law and purposes.
4-2) If your organization has its own network and I.T. staff, there's a good chance they could take steps to determine whether or not you had visited a safeSpace, and when. If they are very determined and prepared to break the law (in most countries) and the organization has lots of money and nothing better to do, they might also be running a potentially nasty product like Bluecoat or Checkpoint. These can be used to allow organizations to read encrypted (https) traffic, and even to impersonate other servers (fingerprint, green bar certificate and all). And who knows, if they're a hyper-vigilant government organization they may even employ Tempest technology. See why we are wary of offering guarantees?
4-3) Here's the thing. Risk assessment is about setting aside both paranoia and naivety. It's about assessing hazards realistically. This involves combining two factors in the right proportion: likelihood and consequences. If you have grounds for concern, and there is no binding agreement in place, we suggest you use safeSpace from your own computer, over your own Internet connection. If your risks are higher still, you might like to invest in a "virtual private network" (more) or, in cases of very high risk, download TOR Tails and select an exit node in Iceland.
4-4) If your life depends on it, do not to use the Internet at all. Seriously. Wait until we all have access to the tools of quantum cryptography.