I download the livery I want,then open The Livery Manager.I click on the appropreate plane , click on the Select Livery to install button.The download pop ups in a new window. I click Select, nothing shows in the box at the bottum.

Are you opening the livery manager in "Run As Administrator?" I believe it needs to opened this way to avoid problems

Didn't help.

I get the livery ok. I go to the Livery Manager and find the livery. I click on the correct catagory (737 nx) on the left side. When the pop up box appears I click select, but nothing shows at the bottom.