OK! Then i will show some pictures! And all in one moment understand my problem!
Here i put on first skin!



Ok first skin is put on and without any problems!That van see below!

And now i will put in second skin

And now i will press open!

Thats all programm turn off! If i be saved game after first skin putting in! Then i can open again model editor and put second skin!
But on third skin again then i will be throw out of program again!
Now i hope any will understand!
And remember im not living in England or Geramnia! And my grammer isnt so great like some others!
P.S. Is some times when progrm in lucky part dont turn off when i want put in two skins but that is quit infrequently!