/wp-content/plugins/
directoryGo to the project page on betterplace.org and look on the URI. The betterplace.org ID is the number after "projects/". For example: http://www.betterplace.org/de/projects/632-kinderhospiz-barenherz-leipzig-e-v This project has the ID 632.
Actualy no. A shortcode feature is planed for the upcoming version.
Just use the dynamic mode of the widget. You have to add a widget area to the template of those pages or use the standart widget area of your Wordpress theme. Then go to the page or post screen in dashboard and enter the corect betterplace.org ID of the project you want display into the box on the right side. May you have to activate this box on the screen options if it is not displayed. After that go to the widget screen and drag and drop the widget area. Then set the widget to dynamic mode and choose display options of favor.