What is causing it to cut out?

Hi Welman, The link below is a short youtube video on how to fix a car that cranks but doesn't start, Also there's videos down the right side that may help as well I hope this helped....CHEERS..
https://www.youtube.com/watch?v=064Ilsz8Fzg
Fixing Car That Cranks But Doesn Start Up

check heater plugs ,it will take around 20 second if heater plug is
not working one or more it will take 10 second . you can S.W ON and off many time so. the engine warm.then try to start

From the Haynes repair manual:
'access to the relays can be obtained after removing the drivers side lower facia then remove the two plate screws (one either end) and lower the plate complete with relays'. Some relays are at the rear of the engine (the second box left to the nearside suspension strut) as your looking into the engine (under a cover)

The fuel pump works off of these fuses/relays:
Pin 5 goes to fuse no. 32
Pin 10 goes to fuse no. 34
Fuses are fed from relay no. 109

Hope this helps, a diagram of the footwell is here:

http://pics2.tdiclub.com/members/MIGOLFGLSTDI/footwell.jpg

dear . start engine then shift revers gear , apply brake then refill ATF more till its full , then shift at P . road test , check how , all problem
ATF was low level

first fill up fuel filter with diesel . then loose injector No3 pipe
and start engine until diesel comes out .

You haven't given much detail about the car but long crank is normally associated with flooding. Dying out as well may occur due tyo too much fuel. CHECK FOR THAT.

On this website you find fuse box diagram and description for Skoda Octavia (2009)

http://www.autogenius.info/skoda-octavia-2009-fuse-box-diagram

sounds like sticking EGR valve to me but ned more info