‘enable in TFGM” means the normal mode (not “Enable legacy mod…”).
Train Fever now have official support for mods and you have to select inside train fever what mods to have active when playing. TFGM only prepares the mods for TF’s internal manager (for now).
In TF, if you click on the “advance” tab, just below the Europe and USA DLC icons you will see two list windows. One with available mods and one with Active mods.
You need to activate the mods you want to use.