I made a few screenshots and put them in links to explain my problem. Thx!
I'm in MR22, the matchcode is not a standard one.
Link: [http://i698.photobucket.com/albums/vv348/su_blimo/screen1.jpg]
I click on F4 for the material
Link: [http://i698.photobucket.com/albums/vv348/su_blimo/screen2.jpg]
I Click on OK
Link: [http://i698.photobucket.com/albums/vv348/su_blimo/screen3.jpg]
I get a list of materials and doubleclick on one
Link:[http://i698.photobucket.com/albums/vv348/su_blimo/screen4.jpg]
The material doesn't show up??!!