1. This forum is about xiaomi.eu custom ROM, is not an official Xiaomi forum.
2. Use an USB 2.0 cable eventually between your PC and phone connect an USB 2.0 hub to force a slower connection between PC and your phone.
3. Try to flash again your phone using a command prompt terminal and one of the shell script from the root folder of your ROM image, in that way you will see the flashing process on the terminal window.