At the bottom of the file in the timed_choice_visual screen, you'll find the part of the bar that fills up.
If you change the xalign to 0 instead of 0.5 the bar will anchor to the left to shrink in that direction.
add Solid(gui.timed_choice_timer_bar_fill_color): at transform: xalign 0.0 xzoom 1.0 linear adjusted_time xzoom 0.0