The game freezes when the map goes from 99:59:59 hours to 100 hours.
The mod Tech tree plus (1.6.3) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event tech_tree_plus::on_nth_tick(60)
tech_tree_plus/control.lua:2638: attempt to index global 'event' (a nil value)
stack traceback:
tech_tree_plus/control.lua:2638: in function <tech_tree_plus/control.lua:2630>

Thanks for catching that.
Should be fixed in 1.6.4

Thanks , I didn't want to uninstall this mod.