Accessibility access, shortcut conflicts, and the usual suspects.
Klipto presses ⌘V for you, and macOS only allows that with Accessibility access. Open System Settings → Privacy & Security → Accessibility and check that Klipto is in the list and switched on. After an update the switch sometimes needs to be turned off and on again.
The item is on your clipboard either way, so a manual ⌘V always works.
Another app probably holds it. Klipto warns about collisions with its own shortcuts, but it cannot see other apps'. Try the combination in a text editor: if it does something else, that something else owns it. Change one of the two in Preferences.
⇧⌘V is a special case — many apps use it for "Paste and Match Style". Klipto takes precedence while it is running.
Images copied from an app are kept as files inside Klipto's container and survive restarts. An image copied as a file from Finder is read at the moment you copy it. If a picture is missing, it was most likely removed by the storage limits — check the maximum size and age in Storage.
Preferences → Clipboard and popup → position. The choices are at the pointer, in the centre of the screen, or under the menu bar.
Write to [email protected]. It reaches the person who wrote the code, and a line about what you did and what happened is enough to start.
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