I have been strugling a bit until I figured this out, so I thought it would be worth sharing it with the community.
It seems that the web runtime will only work with google's Chrome if you also have Firefox installed. I have verified this with several computers and it is reliably happening in all machines I tried it on. So it seems that something weird is going one there that makes it necessary to have both browsers installed. So, until there is a fix for that, you know the work around .