I have created a custom post type which can be seen here: https://gist.github.com/4712f5882d5d719c189f
1. The custom post type supports “Thumbnail” (See line 51).
2. When fundraising plugin is enabled, the admin section does NOT display the “Set Featured Image” option.
3. “Set Featured Image” DOES display with all other plugins wpmu plugins (so far).
4. “Set Featured Image” does display when fundraising plugin is disabled.