Ok,
you should change this param at the dotlrn package:
default_class_instance_applets
and add your SC name implementation (i.e. dotlrn_evaluation).
Notice that it *must* be changed at the APM package parameter, and NOT to the main instance parameter /dotlrn (through the site-map).
Then, for setting it to an specific page, you must add also an specific param, in your case one is: evaluation_assignments_portlet_force_region, and it will be a number which indicates in what page you want to put your applets. (have a look in other portlets)
Remember that this param will be called usually from *-portlet-procs.tcl usually at:
*::add_self_to_page
specifically within this proc:
portal::add_element_parameters \
...\
-force_region [parameter::get_from_package_key \
-parameter "evaluation_assignments_portlet_force_region" \
-package_key [my_package_key]] \ .....
Finally, remember to make your portlet without automount value at the package main information (.info).
