I’m not aware of any Tahoe-specific issues with Capo, but it’s still very early days. I haven’t personally encountered any major issues running Capo on Tahoe since the first beta (we’re on beta 8 now), but I haven’t been running the store version of the app—most of my time in Tahoe is spent reworking Capo for the new design on macOS.
The main change for macOS Tahoe is that I’m getting rid of the Heads-Up Display at the bottom of the window, along with its fiddly Control Strip. Instead, Capo will now (finally?) take advantage of the standard toolbar system, which is fully customizable.