this program is great, for any age, as it is really only limited by your imagination, a few specific pieces it doesn't include (especially if you are picky about color), and the computing power of your pc if you're going to build something massive. my first model was a large two-story plantation-style home sized for lego people (why start easy? xd;; ) and i learned quite a few things about the program due to working with something so large-scale right off the bat.1) the program gets very finicky about trying to stack or combine highly-complex models, or add a less-complex item to a complex one. it will tend to drop things "under the world" or, ironically, if you are trying to put it under the other object, it will send it to the top instead... psychic program? o_o;; i worked on the house model in three separate files (first floor, second floor, attic/roof) as well as bits of it in other files, and eventually ended up having to disassemble and reassemble the upper floors bit by bit onto the rest of the house (though some sections moved in larger bits, like walls). i did it that way to cut down on lag while building the sections, but it made things more difficult in the end.2) the parts selection lacks large flat "bases" in most colors. if you want a big white floor, look foward to putting together a lot of smaller white segments. if you're not picky on color, there's better selection in the black section.3) parts versus color can become an issue, as depending on what build you download, you are limited to what can be purchased at lego.com as opposed to "i want any piece in this database to be whatever color i want it." that's because lego is trying to get you to buy what you create. they can't sell you a part they don't have in stock... which is too bad, because total control over color would be really nice when using the program to make pretty renders of lego-shaped objects.4) as far as i can tell, there's no way to permanently group pieces together. you can ctrl+click to select more than one block, or drag the mouse to get a whole bunch of pieces selected at once. that's all though, which is sad because it is a feature that is sorely missed. a basic lego person has three parts all on its own, and unless you select all three parts at once, you're only going to move the part you clicked on. you can see how that would get tedious with more complex models.5) i managed to lose a save file at one point, so i recommend saving a backup file as well (just remember to go back to working on the real file!). thankfully i was already doing that. what happened when i lost the file was that i saved the main file, then saved over its old backup file, then went back and saved again very quickly over the original file. my guess is it was still saving the original file, and thus got messed up and for some reason deleted the whole thing like it wasn't even there. so yeah, respect the "save as..." menu option. it's a little picky.6) there's no "recently opened projects" list for convenience in the menu.7) the camera can get a bit glitchy, especially on a complex model. you'll be trying to maneuver it to position things on the screen just right and suddenly it'll be looking at the object from a different angle. (and being as it took me a while to figure out, you can change the camera's center-point using the shift key and dragging the mouse. this is very, very important with anything big.)and that's all i can think of. i captured footage of my project with fraps and will be posting it to youtube under the same username. lego digital designer is a great way to show off things that would be a lot harder to render in a true 3d program, though honestly i want to call this program a 3d rendering program. yeah sure it's lego but i can now show people a great approximation of what my roleplay character's house would look like if it actually existed! ^^ i look forward to many further projects in building now that i'm no longer limited to the bricks i actually own.p.s. i'm 31 years old.