Bright,
LinkedIn recently updated their widgets, and the setting for width has been removed. There is no CSS or other way to control that module other than the Display Mode and Display Behavior settings now. That can let you have a very small display area that expands when clicked on. However, there is no longer a way to set the width of the Member Profile. For all the options, you can see their configuration tool, which doesn't have too many options:
developer.linkedin.com/plugins/member-profile-plugin-generator
Hope that helps explain,
Alex