Upload problem with some browsers

Dear support, 
I'm evaluating this product and this is very interesting. 
But I found some problems durign the file upload with Firefox 3.0.3 (VISTA) and the SAFARI browser (on the MAC OSX platform): during the upload the system said [Errore], in te status. 
Can I activate a debug ? Where ? 

Thank You very much. 

Mirko

You can set Debug property of the control to true, to see if you get a detailed error message.
However, there shouldn't be any problems with those browsers.
You can also set UploadMethod property of the control to Browser and if there is no problem then the problem would be only specific to Flash upload mode (default).