Trigger advice

I want to put a lay or back bet, only when my selection's Starting
Price In PLay increased 5 ticks.

 Need I use a 'remember' trigger to 'record' the SP?
  Or is it sufficient i use a remember trigger for my selection?

  I now use this as a condition: and fitting selection's back/lay
price is actual_sp+5, can this work?

To make it 5 ticks not decimal odds of +5  use:

r_ticks(actual_sp,5)

Great, thanks Alfaman, I'll give it a go....

  Nope, it keeps backing immediately when game goes IP, not waiting till the price has moved.

Any more tips? very much appreciated.