When you install Servoy in combination with the Java Runtime Environment 1.6 update 26, you might notice that the file open dialog will not appear in the Developer.
This is a bug in this version of the JRE and has been reported (see https://bugs.eclipse.org/bugs/show_bug.cgi?id=349387 and http://bugs.sun.com/bugdatabase/view_bu ... id=7056092).
I recommend to use an older version of the JRE until this problem has been resolved.