What do you need to know? Does your installer not help?
Fire questions I see if I can help. Depends on your system but probably need to cut in a motorised valve controlled through a room thermostat in your conservatory.
Again dependant on your boiler position and pipe runs there would be two options, heating on in house then conservatory avail and the trickier option of conservatory on independant of house. Combi or system boiler in your house?
Would a cheaper option not be heated elements under the tiles? Although when either breaks your pretty much gubbed. What size on conservatory?