Acorn Installation Guide
Purchasing and installing Acorn directly from Flying Meat
If you haven't already, take advantage of Acorn's 14 day trial period by downloading it from the Flying Meat website: http://flyingmeat.com/acorn/. Click on the button that says "Download and Try Acorn", and Acorn will be transferred over the Internet directly to your Downloads folder. Once that's done, navigate to your Downloads folder and find Acorn. If your browser didn't unzip the Acorn file for you, you might have a file named Acorn.zip - double click on that and OS X will unzip the file revealing Acorn.app. Double click on Acorn to launch it and you will be asked if you want to move Acorn to your Applications folder.
After using Acorn and deciding that it's right for you, you can purchase Acorn directly from the Flying Meat secure website: https://secure.flyingmeat.com/store/. When the purchase is complete you will receive an email with registration information which will unlock the trial period for Acorn. To enter your registration information, launch Acorn and choose the Purchase ▸ Enter Registration Information… menu item. In the window that comes up, enter your registration information (copy and paste works best). If you ever misplace your registration you can retrieve it from our website: http://www.flyingmeat.com/support/.
Purchasing Acorn from Apple via the Mac App Store
You may also purchase Acorn from Apple via the Mac App Store. To do so, open the App Store on your Mac, and search for Acorn. To purchase, click the 'Buy App' button in the App Store. You will then be presented with a button to 'Install'. Click 'Install' and Acorn will be placed in your Applications folder.
When Acorn is purchased from the Mac App Store, it does not require a registration number. If you previously were running the trial version of Acorn, you will need to delete the trial from your computer. Perform a spotlight search for "acorn" (without the quotes). Delete all copies of Acorn. Install or re-install Acorn from the Mac App Store. It should be listed under your 'Purchases' tab. If you clicked the 'Install' button and Acorn isn't showing up in your Applications folder once it has completed installing, try re-booting.
Previously purchased Acorn from the Flying Meat Store and need to re-install
Here is a list of links to download older versions of Acorn. However, you should always be running the latest version of Acorn since it has important bug fixes that older versions do not contain.
Acorn 1.5.5, for use with 10.4 and later: http://flyingmeat.com/download/Acorn-1.5.5.zip
Acorn 2.6.5, for use with 10.6 and later: http://flyingmeat.com/download/Acorn-2.6.5.zip
Acorn 3.5.1 for use with 10.6 and later: http://flyingmeat.com/download/Acorn-3.5.1.zip
Acorn 4.5.8, for use with 10.8 and later (and accepts Acorn 5 registrations): http://flyingmeat.com/download/Acorn-4.5.8.zip
Acorn 5.6.6, for use with 10.10 and later (and accepts Acorn 6 registrations): http://flyingmeat.com/download/Acorn-5.6.6.zip
Acorn 6 is currently the only version for sale and can be run on 10.11.4 and later. Click where it says 'Download a 14 day Free Trial” on this page to use Acorn 6: http://flyingmeat.com/acorn/.
Acorn will be placed in your Downloads folder. Open up your Downloads folder and drag and drop Acorn into your Applications folder. Open Acorn and enter your registration information. If you have misplaced your registration you can retrieve it here: http://www.flyingmeat.com/support/.
Previously purchased Acorn on the Mac App Store and need to re-install
Open the App Store application on your Mac. Log in to your App Store account if you aren't already logged in. Click on the 'Purchases' tab located along the top of the window. If you previously purchased Acorn it will be listed there and you can click 'Install' to have it downloaded directly into your Applications folder.
If Acorn is not listed in the Purchases tab, make sure you are logged into the account that purchased Acorn. You can change accounts using the Store menu item.