the 2C diesel in NA form cannot get the corolla to 200 km/h. The gauge is there to cover most model ranges.
anyway - the slow fighting to start engine is always a sign of a badly timed injection pump, if you have too much advance the engine will fight the starter action as the injection is happening too early - it will also be too diesely (rattling) when it does start. The plunger on the pump advances the camplate in the pump to start early delivery of fuel, it moves the timing about 10 degrees advanced and also raise the idle speed about 300 rpm, it should automatically release itself when the plunger lines get hot (its actually a thermostat) and the timing should come back to normal along with rpm settling to correct idle speed.
by your posting it seems that your diesel lab did not do a good job at all, if they had a test bench AND KNEW WHAT TO SEE, they can actually see the start and cut of injection, delivery volume, action of the said plunger, measure internal pressure of the pump, leak down etc. The nozzles also play a very important role in timing the engine, if one nozzle has low break pressure compared to the rest - that certain cylinder will fire with advanced timing and vice versa if the pressure is too high.
The correct procedure to adjust pump timing is to use a dial gauge on the pump when installing it to the engine and pulling the cold start advance to disengage - the aim is to lock the pump at 0.8mm stroke of the plunger when the engine is at dead zero TDC of cyl no1. You cannot achieve this with "andaaza" unless you actually are God.
I cannot help you in Pakistan as I live in USA now, I had all tools to adjust such diesel engines in my shop in Pakistan but most (read 99%) of fresh ustaadified customers did not want to pay my required fee to adjust and calibrate their car's engines.