Was able to solve it finally last night!
The pins must not be defined as GPIO pins or numbers. as discussed here before.
If CLK is connected to D6 and DIO is connected to D5, exactly as written on board.
#define CLK D6
#define DIO D5
But there are many faulty libraries that dont work with my board set. Could get only one example for Number Flow to work. other examples from this and other library do not function for me. So I will take this now as the base, simlify it and add what I need to buid the actual project.
It is really sad, that there is difficult to find a complete datasheet for the display, but it actually is Min voltage 3.3V, Typical 5V and Maximum 5.5V. Connected to VU will give more brightness (If set BRIGHTEST in code) out as it is 5V coming directly from USB (not connected with ESP).
Sorry @Gunner for this last post, but i made this to help users in the future if they search for similar issues. Will come back with Blynk related issues only in the Future