[r8300] Crash on Changing Minimum load in schedule

[Fifty]

1. Open a new schedule window
2. Press "Insert"
3. Add some stops (Note that none are highlighted/selected like if you use "add stop"...this is likely the culprit)
4. Press one of the arrows to change Minimum load
5. Kaboom! (error message attached).

[Dwachs]

should be fixed in r8301, thanks for the report.