Back when I had my MK3 ibiza cupra 1.8T I was stopped in traffic when it over heated, that turned out to be a blown fuse on top of the battery box, replaced the fuse and topped up with coolant and never had a problem.
With the LCR I'd be changing the temp sender and thermostat to rule out 1st. With mine I checked the water pump and got that replaced too. Other thing to look at are the fans, I noted mine heating up in traffic a few years back and replaced the fans as small fan wouldn't work all the time, purchased them from Euro car parts, never had a problem since.
With regards to loosing coolant check the pipe from turbo to coolant res, mine was leaking due to age.
With the LCR I'd be changing the temp sender and thermostat to rule out 1st. With mine I checked the water pump and got that replaced too. Other thing to look at are the fans, I noted mine heating up in traffic a few years back and replaced the fans as small fan wouldn't work all the time, purchased them from Euro car parts, never had a problem since.
With regards to loosing coolant check the pipe from turbo to coolant res, mine was leaking due to age.