More than you’ll ever want to know about Grids + Guides in Catalyst.
You want grids and guides in Catalyst?
Well, we've got them.
This post is a simple rundown with some grids/guides tips and tricks... I mean, I need a break after that optimization post... right? 
Creating An Image Gallery Using a Data List
Ever wanted to create an image gallery with more than 20 images? Ever wanted to play some more with Data Lists in Catalyst? Well, here's your chance. We're going to create an image gallery using Data Lists and the Design Time Data Panel, so that you can create an image gallery with as many images as you want. The end result of this tutorial will look something like the below image.
More after the jump.
Setting the initial position on a scroll panel
If you've been playing around with scroll panels, you've probably noticed that the scrolling content window always starts off displaying the upper left corner of the actual scrolling content. Great for anything text-based, but not so great for anything image-based. For example, if you're scrolling an image, you will probably want to start out with the content window displaying the center of your content.
Example 1 (Centered Content)
Example 2 (Default, Top-left Content)
More after the jump!
Creating Scrollbars without Tracks and Thumbs
Have you ever designed a scroll panel or data list and wanted to make it scroll with just buttons? For example, the scroll panel below scrolls its content with just an up, down, left, and right button.
Normally, when you create a scrollbar, Catalyst prompts you to assign the thumb and track for each scrollbar. In fact, they are both marked, rather ominously, as "required". One way of getting around this is to create the thumb and track parts, and then hide them, either offscreen, or setting their opacity to zero. But this can leave weird mouse interaction areas in your swf, and it's less than ideal.
As it turns out, "required" parts for the horizontal and vertical scrollbars are really only suggested. They're part of a typical scrollbar, but in this case, we don't want a typical scrollbar. So guess what? You don't have to assign them. Just assign the button parts (left, right, up, down) and you're good to go.