Garmin POIs: bizarre interaction with colour scheme

I've just been trying to use Garmin's POI-Loader with a 60CSx, and found that the "Find - Custom POI" function always turned up nothing. Then I read on another forum that somebody had found that Custom POIs were only visible on a Vista Cx when certain colour schemes were set. Now I have found the same with a 60CSx:

Custom POIs are only visible with the Amethyst, Diamond, Emerald, Sapphire and Topaz colour schemes.

This strikes me as extremely odd. Has anybody else seen anything similar?

-Tim
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