Hi, I gues there is an typo on p107 :)SET AUXILARY COLOR $900E POKE 36878, AUX_COLOR + VOLUME_0-15
sould be:
SET AUXILARY COLOR $900E POKE 36878, AUX_COLOR * 16 + VOLUME_0-15same as at the border / Background color.
Character color *16 is correct ... but <aux color> refers to the preceding table with the aux numbers listed.