macOS blocks the first open
Use the download from CubbyPad’s own site, move it to Applications, open it and click Done on the macOS message. In System Settings › Privacy & Security choose Open Anyway for CubbyPad and confirm. The installation guide has the complete sequence.
The shortcut opens Spotlight
Use Shift–Command–Space until Spotlight’s Command–Space shortcut is disabled in System Settings › Keyboard › Keyboard Shortcuts › Spotlight. Make sure CubbyPad is running and check the shortcut in Settings › Opening.
It does not start after a restart
Keep CubbyPad in Applications rather than launching it from the DMG. Open it once from there and check Open at login in Settings › General. If it opens to License instead of the grid, check activation there.
The pinch or F4 opens something else
Turn on the relevant control in Settings › Opening. CubbyPad uses a three-finger pinch; macOS’s thumb-and-three-fingers gesture is different. F4 is remapped only while the CubbyPad option is on and the app is running.
Still not working?
Email support with the macOS version, CubbyPad version from Settings › General, the steps you tried and what you expected. A screenshot or short recording helps. Do not send your full license key. More specific answers remain in the full Help reference.