What version of
PowerDesigner are you using? What version of mysqldump are you using? There are a number of conflicts between the mysqldump scripts and older (pre-2010) versions of PowerDesigner and a few issues still exist in v15.2 with some mysqldump files.
PowerDesigner will always present error messages via the GUI and in the log. What are you getting when you try to import the dump file?
-PatP