SuperCard 4.8.1 remains 32-bit. Unfortunately, producing a 64-bit version of SuperCard requires a complete rewrite of the software as Apple has gone back on their promise to deliver 64-bit Carbon frameworks. This is a tremendous undertaking, and while the current version has made some inroads in this regard, currently it is unknown how long it will take or if it is even possible.
SuperCard is currently natively compatible with any Mac running macOS versions Tiger thru Mojave, so we recommend holding off upgrading your Mac to Catalina. For users that must upgrade to Catalina, we have confirmed Parallels 15 is compatible with Catalina, and can host a Virtual Machine with an older OS version that supports SuperCard.
We have prepared a video tutorial outlining the process of creating a virtual machine using Parallels Desktop, and installing a guest OS to run SuperCard. The process is quick (not including macOS download and install time), easy, and SuperCard performs quite well in this environment.