There are two Open extensions in KeyQuencer: Open always works, while OMOpen requires that both OtherMenu (a great shareware system extension written by James Walker) and KQ Apple Events are installed. There are many other differences, although some of the things they do are similar.
Open can open applications, documents, folders, aliases, aliases to network disks, control panels and anything else you can double-click in the Finder. In fact, since Open sends an "open" command to the Finder, opening an item with Open is much like double-clicking it in the Finder itself. Open can also bypass the Finder and launch applications directly (including background-only processes such as KQ Apple Events itself or the File Sharing Extension, or even invisible applications that can't be seen in the Finder) when you add the "application" parameter. You may execute text macro files created by the Macro Editor by using the "macro" parameter; the macros are executed on the local Mac, since network operation requires the Macro Editor. If you want to execute macros on a remote Mac, you should omit the "macro" parameter; the Finder then launches the Macro Editor, which in turn sends the macro to the target machine. The "clipboard" parameter gets the file to open from the clipboard text, which must contain a full pathname (something like "My Disk:Documents:Text Files:Letter").
OMOpen sends the "open" command to OtherMenu rather than the Finder. OtherMenu can then open files, folders and aliases via the Finder just like Open does; but OtherMenu does a lot more than that. It can execute its own external commands, which include many useful items, execute AppleScript compiled scripts, change the current directory and file in the standard directory dialogs and much more. Please read the OtherMenu documentation for detailed information about OtherMenu.