So, you want to get APRO, APAX or APRO-CLX. You'll need to download it from Source Forge, which is a storehouse of all things open source. You will probably want to set up an account there to gain full access. If you choose not to register with Source Forge, you can still download the files but you won't have access to the other useful stuff (newsgroups, email, etc).
To set up a new account with Source Forge:
Go to http://sourceforge.net/ and click on the "New User via SSL" link in the top-left of the page. That will bring you to their registration page where you should fill in the required information. Once you do that, click the "Register" button at the bottom and you'll get an email verifying the info. Click the link in that email to get authorized. If this gets too confusing, see https://sourceforge.net/docman/display_doc.php?docid=11123&group_id=1.
You'll notice that APAX (the Active X version) is not specifically referenced here. That's because it is too tightly bound to APRO. You'll find the APAX OCX in the APRO\BIN folder, and the source in the APRO\APAX folder. If all you want is the latest version of the OCX, go to the "View ALL Project Files" link and download the bin file. That will contain all of the binaries (the APAX OCX, printer drivers, etc)
Note that you do not have to be a 'developer' for the project to download the files. If you want to contribute to the projects, you will have to register as a developer. You also do not need to go through all of the CVS stuff, unless you want to become an active, contributing maintainer.
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