The transformation using fleximage is performed by the controller - look
at:
Transformation is specified by .flexi view files. Examples in my
repository:
http://soxbox.no-ip.org/radiant/svn/extensions/part_assets/app/views/admin/attachment/admin_thumbnail.flexi
http://soxbox.no-ip.org/radiant/svn/extensions/part_assets/app/views/site/attachment/default.flexi
http://soxbox.no-ip.org/radiant/svn/extensions/x_groggy/app/views/site/asset/article.flexi
http://soxbox.no-ip.org/radiant/svn/extensions/x_groggy/app/views/site/asset/feature.flexi
You need to install the fleximage plugin also:
http://beautifulpixel.com/svn/plugins/flex_image
Dan.