You could also substitute the following code line (line 91 in version 1.2.1)
$this->modx->regClientCSS($this->gallery->config['assetsUrl'].'packages/galleriffic20/css/galleriffic-2.css');
with this one:
$this->modx->regClientCSS($this->gallery->config['assetsUrl'].'packages/galleriffic20/css/'.$this->modx->getOption('gallerifficCss',$this->config,'galleriffic-2.css'));
Then you can use the parameter &gallerifficCss like:
[[!Gallery?
&album=`My Album`
&plugin=`galleriffic`
&gallerifficCss=`my_gallerific.css`]]
This allows usage of different Gallerific layouts in a website ;-)
In case splittingred reads this, maybe could you consider adding this in a future release ?..
Regards