Thanks for reporting this. I am able to reproduce it and will look for a solution.
Just to inform you that DbVisualizer 9.5.6 has just been released with a fix for the issue you reported..
Easiest is that you open Help->Check for Update in DbVisualizer to perform the upgrade.
An alternative is that you download from our web site: http://www.dbvis.com/download/
When I right click on a schema, choose export, choose "functions" and then this function:
I get the following error when clicking on "export":
I'm running DbVisualizer Pro 9.5.5