Sorry, it doesn't stay indefinitely. We'll change it in the next build. If you know Javascript you can do it yourself by modifying aware.js. Locate this code:
this.m_hoverTip = new Ext.ToolTip ({
...
});
You need to add dismissDelay property in miliseconds to this object:
this.m_hoverTip = new Ext.ToolTip ({
...,
dismissDelay: 10000
});
This sets it to 10seconds. dismissDelay: 0 sets it to indefinite. Default is 5000 (5 seconds)