Me again

Now I have a new problem, on cold start before the maschine turns to working temperature, rpms jumping around 800-1200 for a few seconds. Then after a half of minute everything is normal, needle stops at 1200rpm and when it get hot turn down to 800rpm.
But... the real problem is, when I want to stop on a red traffic light and squeeze the clutch together with the brake, the rpms are falling down to 0 or 200rpm and sometimes the engine turns off.
After a few kilometers when it gets really hot there's no any problem.
My mechanic tried to clean the idle controll unit but no luck.
Thanks in advance
PS
This forum solved many of my questions before and it is good to know the helpful place on a web like this is.
I can't use google translate and be logged in at the same time? So it is difficult to find posts what I'm looking for.
I tried to download a whole site xedos.ru for personal archive but also it cannot use google translate when downloading because I must be logged.