Hi
basically you need to measure the price movement or tick difference over a certain period of time
very short-term, i.e. over one refresh, look at the conditions:
selections back price leap
selections lay price leap
selections back price growth
selections lay price growth
to measure a price difference over some minutes use:
selections back price dif over xx mins
selections lay price dif over xx mins
selections back ticks dif over xx mins
selections lay ticks dif over xx mins
example, if you want to back the favourite if it's back price has come in at least 10 ticks in the last 5 minutes:
selections rank is equal to 1
and selections back ticks dif over 5 mins is equal or less than -10