Just for future generations, in case someone is looking at hot start issue, which is fairly common - an issue and diagnosis.
The symptoms: difficult hot start. Car running ok, starting cold in 3 seconds after several weeks of parking, etc. Just would crank and not start when hot - neither after 10 minutes nor after half an hour.
The issue: restricted fuel supply through the main supply line.
How figured out: first was to look if spark plugs are wet or dry while cranking to try to start the engine. They were dry. Then measuring fuel flow right after the fuel pump and then at the main filter showed low flow at the fuel filter and a very good flow right after the pump. Could not detect it by blowing air through the line. Only by checking the fuel flow.
Hot start ok once the obstacle was removed. I will not write what the obstacle was, because everybody would laugh at me.
Note: for those who have the TTS replaced by the Bosch unit - please note it activates the CSD at all times, also when engine is hot (it just does it for different amount of time or just when cranking, depending on temperature). May consider not to depress gas pedal when starting or depress it just slightly.