Hi, 
Since my last post,I found a procedure to make it freeze. 
for me it freezes when : 
- the project is a bit complexe (try with somethink like Heloword, never freezes   ) )
- enter a symbol (or namespace ...)  in the code 
- When the completion proposal appears on the screen, hit some backspace and change the symbole.
On some project it freezes immediately
I tried just now to disable "Symbols Browser" , looks ok.
so i closed CB and run it again, re-enable  "Symbols Browser"
and it didn't freeze for the moment.  

I'll will test more, and I'll get back to you.
thanks for your attention