Moving load command by staadpro

[handlllll]

Is any body can help me with staadpro command.
I have sent this problem to staadpro but no answer as usual.
my problem starts with a simple beam with 2 simple supports and I have a
span of 20 ft long ,load is 5 kips acts vertically. what I want is to
calculate my max. bending moment and the location using moving load
command.
the answer will be 5/2x20/2 = 25 kip-ft acts in the mid span.
if you are going to help me please do not apply self weight in the
calculation

 

[handlllll]

I have received this answer from staad-pro supports.
it works but when I play around changing numbers for xinc from 1 to 0.2 i get different answer which I do not understand , I am waiting for their answer.the command was
DEFINE MOVING LOAD
TYPE 1 LOAD 5 0.0001
DIST 0.001
LOAD 1 MOVING LOAD
LOAD GENERATION 20
TYPE 1 0 0 0 XINC 1
STAAD expects minimum two wheels for defining a moving load.In addition to the 5 kip load please specify another fictitious load of a very small amount, like 0.001 kip placed at a small ditance like 0.1 feet.
Then apply the moving load in a way so that in course of movement it comes at the midspan of the beam.This will create the desired moment at the mid-span.

 

[handlllll]

I think 0.2 is not working because load generation 20 should be 100 instead.
I tried it and it works.