HCL Sametime Forum : Your Sametime Web Plugin install experience?

I have installed and patched a fancy new Sametime 9 demo environment to test out which web-browsers that are usable with Audio/Video and Screen Share with Meetings.

So far it has NOT been a good experience.

I have put in this option in Meeting server to use plugin instead of Java to share screen:
appshare.plugin.windows.enabled true

This is what I found out googling this issue:
No 64bit browsers seems to install the plugin.
Chrome has disabled plugins so no sametime plugin, I will test this anyway.

On Mac running Mac OS X 10.10.3 both Firefox and Chrome are 64-bit by default, so here there is a no go for the plugin anyway.
But
Safari seems install the plugin and it works!

On Windows 10 ( a virtual machine )
* Chrome (seems to be 32bit) does not prompt for any plugin. But when I try to do screenshare I asks to install Java.
* Microsoft Edge does not promt for any plugin. But when I try to do screenshare it asks to install Java.
* Firefox (32bit version 39) does not prompt for any plugin. But when I try to Screen Share it says "A plugin is needed to display this content" which is probably because of missing Java
* Internet Explorer 11 (32bit) - no plugin installed, no prompt to install, nothing happens at all when clicking Screen Share.

On Windows XP (virtual)
* Internet Explorer 8 - Plugin gets installed
* Firefox 39 - prompts to install plugin, it gets installed! Need to restart firefox - OK. Plugin is installed!
* Chrome - Prompts to install plugin, I try this, it downloads but then Chrome says that "Applications are not allowed to be installed from this site"

Could you please share your experiences?
Any help how to increase the possiblility to get browsers on Windows 10 to install the plugin?