Hi,
thanks for your quick answer.
I'll stick on the original right reference with stm..407. It's sound definitely like the wise choice for now on, at least for me.
Having said that the second discovery I have is a STM32F401VC which seems to have the same number of pin as the 407 (don't know what it means but it is 100pin LQFP for both). I start again to hope that could it be done.
At least if it was possible, troubles would not come from this part. I wonder which files are specifically written for the 407 or the 401 for the bootloader to work and if it is only a question of few lines to be change or as you were suggesting something to complex to be updated?