REGEDIT4

[HKEY_CLASSES_ROOT\*\shell\edit]
@="Edit with &SciTE"

[HKEY_CLASSES_ROOT\*\shell\edit\command]
; Adapt path to your...
@="\"%PROGRAMFILES%\\SciTE\\SciTE.exe\" \"%1\""

[HKEY_CLASSES_ROOT\*\shell\print\command]
; Optional, of course
@="\"%PROGRAMFILES%\\SciTE\\SciTE.exe\" /p \"%1\""