HBOOT 1.02 downgrade succeded!
@BlaYo, I agree in your conclusion on your retorical question.
But nevertheless i succeded in doing just that.
The short version:
make Goldcard (GoldCardTool-0.0.5, klutsh.com)
unpack hack4legend-v5 in your C:\android-sdk-windows\platform-tools
temproot...