Support.
Written by the person who wrote the app.
macOS has not granted screen recording yet, so the capture is a blank image. Open System Settings → Privacy & Security → Screen & System Audio Recording and switch Silo Snip on, then quit and relaunch the app — macOS only applies the new grant to a fresh launch. Silo Snip also tells you this in the menu bar when it detects the permission is missing.
Another app almost certainly owns that combination — macOS gives it to whoever registered first, and Silo Snip loses silently by design rather than fighting for it. Open Settings from the menu bar and record a different combination. If Settings shows the shortcut as unavailable, that is the same conflict being reported honestly.
Recognition quality follows the pixels. Small text, low contrast, heavy anti-aliasing and busy backgrounds all reduce accuracy, and a region that spans two columns will interleave them. Zoom in before you snip and drag a tighter box around the passage you actually want.
Settings lets you set which languages Vision should consider, in priority order. Leaving it on the system default follows your macOS language settings, which is right most of the time and wrong when you regularly read a second language.
Nowhere. The captured image is held in memory only long enough for Vision to read it, and then released. Only the recognized text is written, and only to your clipboard. There is no history, no library and no cache to clear — that is the design, not a missing feature.
No, and it will not learn to. Silo Snip stops at plain text on the clipboard on purpose. Ohms Lens does tables to CSV and design tokens; Ohms Explain decodes barcodes and QR codes and answers questions about what it sees. Use those when you want more than the text.
Yes. The crosshair covers every connected display, including different scale factors, and the capture is taken at the resolution of the display the region is on.
No, and it cannot use it. The app ships with no networking entitlement, so the sandbox refuses outbound and inbound connections outright. There is no account and no telemetry.
Include your macOS version, which Mac you are on, and what was on screen when it went wrong. There is no account to look up and no telemetry to consult, so what you tell me is all I have.