PrimerSelect 8.1.4 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This software for Mac OS X is a product of DNASTAR, Inc. The application is included in Education Tools. The following version: 8.1 is the most frequently downloaded one by the program users.
From the developer:
PrimerSelect was the first primer design application within Lasergene, and has now largely been replaced by the primer design capabilities within SeqBuilder. However, we still include PrimerSelect with every Lasergene system because it can be useful for some advanced primer functions, such as adjusting mispriming parameters and creating a primer catalog.
You may want to check out more software for Mac, such as MegAlign, Avogadro or LXVII, which might be similar to PrimerSelect.