[Flix]

А как сделать так же со стандартной кнопкой ("Далее")? »

Вот так, например:

Скрытый текст

Код:

!include "nsDialogs.nsh"
!include "winmessages.nsh"
!include "logiclib.nsh"
OutFile "test.exe"
 
Page Custom pre
Page license
Page instfiles

var dialog
var hwnd
 
Function pre
  nsDialogs::Create 1018
  Pop $dialog
  ${NSD_CreateCheckbox} 0 0 50% 6% "Enable button Next"
     Pop $hwnd
     ${NSD_OnClick} $hwnd EnDisableButton

  GetDlgItem $0 $HWNDPARENT 1 # get handle next/install button
  EnableWindow $0 0           # disable next/install button

  nsDialogs::Show
FunctionEnd

Function EnDisableButton
  Pop $hwnd
  GetDlgItem $1 $HWNDPARENT 1
  ${NSD_GetState} $hwnd $0
  ${If} $0 == 1
     EnableWindow $1 1
  ${Else}
     EnableWindow $1 0
  ${EndIf}
FunctionEnd

Section ""
SectionEnd