This is a one-time alert that warns you that this is a 32-bit application that will require updating to 64-bit if you wish to continue using the latest version of macOS. The 'Learn More…' button links to an Apple Knowledgeable article.
We are looking to release 64-bit versions of our applications during the first half of 2019. This is not only required for them to run on future versions of macOS, but it also enables us to build them with the latest frameworks and development tools.
For some of our applications, moving to a 64-bit architecture is a major task. This is mainly due to the APIs (third-party software) that we use to build our applications with, as these also need to be updated to 64-bit. Some of these APIs haven't or won't be updated, and so we are now re-writing some application features to use a different approach. As you can imagine this can be a time consuming process and it is difficult to predict the duration of the work required.
The 64-bit applications that we release will also have a new operating system minimum version requirement, which is one of the reasons we've held off performing this update. At this stage our 64-bit applications will require:
Mac: macOS 10.9 (Mavericks) or greater
Win: Windows 7 SP1 (64-bit) or greater
We will update this article as we release updates for our applications. Thank you for your support and patience.