Ecobrick is a game written as a GEM application. It includes instructions
for play, but the following observations will be useful.
  Both .APP and .RSC files must be accessible (the sensible thing to do is
to put them both in the GEMAPPS folder), as with any GEM application. It is
run from the GEM Desktop by opening ECOBRICK.APP.
  During the game you are required to design an icon, and once designed,
these icons can be altered. However, this can only be done if the GEM VDI
implements the function v_get_pixel(). The Amstrad 1512 VDI driver, for
instance, does not. In this case the editing screen looks somewhat messy, and
the best technique is probably to edit the icon and immediately click on OK.
This will blank the icon, which can then be edited more easily. (These
instructions will make more sense once you have played the game.) Having said
that, it should not really be necessary to edit the icons once they have been
defined.