I think this plugin does not support the features you are currently using. Here is the code from plugin
/**
* Sets a specific step object by index.
*
* @method setStep
* @param index {Integer} An integer that belongs to the position of a step
* @param step {Object} The step object to change
**/
$.fn.steps.setStep = function (index, step)
{
throw new Error("Not yet implemented!");
};
/**
* Skips an certain amount of steps.
*
* @method skip
* @param count {Integer} The amount of steps that should be skipped
* @return {Boolean} Indicates whether the action executed
**/
$.fn.steps.skip = function (count)
{
throw new Error("Not yet implemented!");
};