You could cycle a certain colour using FLASH and/or SHIFT commands. I'm reading it right now in the AMOS Pro manual, so in the basic version it could be a bit different.
A sentence could be like:
FLASH index number, "(colour,delay)(colour,delay)(colour,delay)..."
where you could define up to 16 differents colors and delays for the cycling.
EDIT: yup, I'm looking now in the AMOS CREATOR manual and FLASH works just the same way!
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