You have to make sure the structure is level and square.
If the structure is not level and square, the door will bind and not move properly.
Purchase a 2 foot level and a plumb bob from a hardware store or building supply.
The centre bubble on the level should be in the centre when you place it on the horizontal framework.
The plumb bob must have a string attached to it which goes through the hole in the top. Hold the plumb bob string close to the vertical corner support by the string. let the plumb bob hange down so it does not touch anything. The string should be the same distance from the vertical corner at the top as it is at the bottom. If it is not the same distance, your vertical corner is not plumb. this will twist the whole structure and cause the sliding door to bind.
im having problems getting the door to slide on