Hi Harry, how are you trying to connect the Flexbus and the TWR-LCD? are you connecting the TWR-LCD module directly to the TWR-K70 board using the primary/secondary elevator connectors?.
Please be advised you cannot do so, the problem is TWR-K70F120M can only interconnect directly with TWR-LCD-RGB since the controller board uses the LCDC dedicated bus instead of the Flexbus, so if you want to use the TWR-LCD you have to manually connect the TWR-K70F120M Flexbus lines to the TWR-LCD module.