Hi David,
Make sure the NETWORK SERVICE user has read permission on the root folder and read/write permission on the /Data folder
Or if you copied a "web" folder into the mysqldev folder then change the site home directory to c:\mysqldev\web
Make sure the Default.aspx file exists in the root, and make sure you have configured all the file masks correctly for UnLeashIt or it may not have deployed all the needed files.
Hope it helps,
Joe