CCJH6.6FT Sliding Track Barn Door Hardware Kit for Single Wood Door,Heavy Duty,T-Shaped Style Black

Is this product easy to use?

You say a 10ft double kit is only good for a 30" opening. But you say of you have a 2ft door.... you need a 4ft kit... Why wont a 10' work for 50"

What is the dimension from wall to the face of the door bolts?

Wooden pieces are used how?