There is only one file type that uses the .NCLR extension:
Nintendo DS Color Palette File
File used by some games for the Nintendo DS; contains a color palette for the graphics stored in a corresponding .NCGR file, which stores the title screen image for a Nintendo DS game; used by games such as Mario Kart DS.
Title screen graphics can be edited with MKDS Course Modifier and Crystal Tile 2.
Updated: October 5, 2012