I was in manual mode, running reverse. Then change from manual to automatic. I want to go foward. Then the message:
"
Error while runnig event
OverloadedTains::on_tick (ID 0)
Trying to change direction of automatic train moving on a path.
stack traceback:
!!OverloadedTrains/control.lua:247:in function
<OverloadedTrains/control.lua:223>
"

Hi
I have the same bug with a great LTN map (and a lot of other mods ^^)

should be fixed now i guess

Just got this. Restarted 4 x times and it did it every time.
The mod Overloaded Trains caused a non-recoverable error.
Please report this error to the mod author.

Error while running event OverloadedTrains::on_tick (ID 0)
Trying to change direction of automatic train moving on a path.
stack traceback:
OverloadedTrains/control.lua:247: in function <OverloadedTrains/control.lua:223>
stack traceback:
[C]: in function 'newindex'
__OverloadedTrains/control.lua:247: in function <OverloadedTrains/control.lua:223>

this shouldn't happen...
yet i implemented a different direction-check which works for me just fine too.
if it doesn't work you probably have another mod that screws with train acceleration
or you're using an older version than 0.16.6

you're right, happened to me too today
i released another update.. should be stable now :/