The timer you have is only a single channel model so I would think that it would be wired so it turns on the boiler at the times set, and then you have to control your heating and hot water with the thermostats.
This timer will not give individual control of CH & DHW They will both come on and go off together.
So I would suggest the following set up.
1, Set the timer to come on 3/4 hour before you get up in the morning,
2, Set the thermostat on the hot water cylinder to 60 degrees C.
3, set the room thermostat to 20 degrees C.
This will give you a full tank of hot water when you get up and the house will be nice and warm.
If you both go out to work time the heating and hot water to go off 1/2 hour before the last person goes to work
4,Set the afternoon time so it comes on 1/2 before the first person gets home, This will give you a warm house and a tank full of hot water when you arrive home.
5, set the off time 1 hour before you go to bed.
You will find that the house will stay warm enough the last hour before you go to bed. and this will save you on the gas bill.
In summer turn the room thermostat down to zero so the heating does not come on.
To test that the system is working correctly carry out the following:
1, start with the system cold.
2, set the DHW stat to 60 deg.
3, set the room stat to zero,
4, set the timer to the on position
5, the the boiler should fire up,
6, the pipe between the three port valve an the DHW cylinder should get hot
7, this will show that the system is heating the hot water,
8, now turn the room stat up to just past the position where it clicks.
9, the pipe to the left of the 3 port valve should now be getting hot and the radiators will start to warm up.
If the above does not happen post back and tell us what does happen we can then advise on what is wrong with the system.
The 3 port valve is the gray box above the round red item which is the pump.
David