Rotating color table object (for easy and consistent labeling)
Minor nitpicks:

None of you keywords are reserved words (especially if it starts with an underscore!) so encasing them in single-quotes is superfluous.

ColorTable.tableSize is an example of the smurf-naming convention (see item 21). Drop the second instance of table to become ColorTable.size

For setIndex you return two different datatypes: index on success, and false for failure. Since index is an arguements known to external code, what purpose does this serve? For consistency, you should return true/false for pass/fail if you have to. If you have to, how about a single point-of-return? You'd have to introduce a variable, and two more LOCs, but... single point-of-return!

But why not throw an exception? The existing mixed-type return suggests that calling code doesn't use the return value in any meaningful way.