"Keychain..." in the drop-down list of "Help" on the tab "Home" is meant to show the Invantive Keychain, which holds the credentials of the databases. In release 27.0 Invantive Studio reports "Keychain dialog not yet available.". The keychain itself is described in [[Invantive Keychain]]. From release 28.0 and its BETA release 27.1 the key combination is `Ctrl+K`.