Down inside your <loadpoint> which is usually something like C:\Program Files\PTC\ProductView Express\preferences\ProductView you should see two XML files and a readme file.
You can edit the preferences for Creo View Express using the XML file. The readme file explains all about it. You can also interactively tweak the configuration settings from the File>Options menu within the application directly.
To change the starting directory, edit the shortcut that launched Creo View Express. Change the Start In location. This will do the trick. Putting your config.pro in the \bin directory will have no effect. That file is only used for Creo Parametric or Creo Elements/Pro (Pro/ENGINEER).
If that's still unclear, just write back and I'll go into more detail.