It's not clear to me which iso you are using. If you made your own iso with refractasnapshot, then the method of installation will depend on what installer you have in the original system. Refracta Installer must run from the live CD/USB system, so you can't run it directly from the boot menu.
If you installed refractainstaller-base, you can just run 'refractainstaller' from a root terminal. For the gui version, you need to install yad.
ttps://sourceforge.net/projects/refracta/files/testing/http://debs.slavino.sk/files-testing.phpIf you put a stock Debian iso onto a usb drive, you can run the installer without booting into a full live system, but your mileage may vary, depending on how to put the image onto the usb stick. Recommended method is to use cat or dd. Then the usb will act like a live-CD when you boot it, and all the menu items will be present.