Welcome to the forum, I suggest you give a little bit more detail in what you wish to achieve, do you mean use the one input (0/0) to turn on lights in succession ? do you need them to come on & stay on or rotate in sequence.
If in sequence then I suggest you use a counter, with an less than function so the counter only counts up to 3 then, reset the counter with the second input.
Use Compare functions to drive the outputs
IO/O
-------| |---------[ LES < C5:0.ACC 3 ]-------------[C 5:0 4]----
IO/1
-------| |-----------------------------------[RST C5:0]
O:0/0
--------[ GRT > C5:0.ACC 0]--------------( )
O:0/1
--------[ GRT > C5:0.ACC 1]--------------( )
O:0/2
--------[ GRT > C5:0.ACC 2]--------------( )
So providing the counter accumulator is less than a count of 3 the toggle of the input will count up, on count 1 the first lamp will come on
on the second count the second light will come on
on the third count the third light will come on subsequent toggle of the input will not do anything
Toggling the second input will reset the counter to zero all lights will go out.
If you only want one light at a time replace the compare functions with EQ.
Then the lights will only come on depending on the counter value.
Sorry I do not have RSL at the moment on this pc, hope this helps, there are of course many other ways of doing it by sequence bits or words.