It appears plugins cannot currently change the FFB output. The incoming value can be read (-1.0 to +1.0 in rF2, which is good to see after the user-adjustable maximum in rF1 with a default of 11500) but setting that value (and returning true, as per instructions) has no effect. rF2 has great FFB, no doubt. So there's been little call to have plugins developed like there was in rF1, and that's fair enough. There may, however, be times when adjustment of the FFB is warranted beyond what the game offers, whether it's hardware specific or to user preference. So, please switch this back on.