It's easy to learn. Chuck (the script's author) has put together a huge pile of fantastic instructional PDFs and videos on his website. The in-product help is also comprehensive and well-placed.
It's easy to use. Everything's right there in the Plugins menu, so you don't have to memorize and keep track of a bunch of little tool icons. The input method for telling the script where to put gables and sheds couldn't be simpler.
To use Instant Roof, you select a face and choose Plugins > Instant Roof > Make Roof. In the following image, I chose to use the California Ranch roof style:
Jeremy, not sure what happened to your download, I just downloaded the script, installed it and in less than 5 minutes, I had a roof. I use SU7 free. Try again just draw a simple rectangle then select the top face, go to plugins menu click instant roof, pick a style, and OK the default settings work fine for now.
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