A Guest account should be added to the webapp to make it more in line with the desktop client. Currently to have a guest connect to a system, they would need to use the full software.
Your guest can join your meeting (or call you) with Chrome using the following URL: https://manage.lifesizecloud.com/#/call/[extension]
I agree with you though, a guest option like the desktop app would be simpler.
Guests can connect today by using the new webapp. Due to recent changes to Chrome the original webapp can no longer be used. Here is a post with the details:
WebRTC Client: Failed to connect
To Kevin's point below, the address is Lifesize Cloud Web App
This is the page that that Chrome users are sent to when they are invited to a call from the call me page and they choose to call from their browser. https://manage.lifesizecloud.com/#/call. We will be releasing this for Internet Explorer 11 users shortly.
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