My main save game as well as all auto saves are broken. When trying to load:

The mod Transport Drones (0.5.7) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event Transport_Drones::on_load()
LuaEntity API call when LuaEntity was invalid.
stack traceback:
Transport_Drones/script/depot_common.lua:204: in function 'get_lib'
Transport_Drones/script/depot_common.lua:209: in function 'load_depot'
Transport_Drones/script/depot_common.lua:349: in function 'on_load'
core/lualib/event_handler.lua:74: in function <core/lualib/event_handler.lua:70>
stack traceback:
[C]: in function 'index'
__Transport_Drones/script/depot_common.lua:204: in function 'get_lib'
Transport_Drones/script/depot_common.lua:209: in function 'load_depot'
Transport_Drones/script/depot_common.lua:349: in function 'on_load'
core/lualib/event_handler.lua:74: in function <core/lualib/event_handler.lua:70>

Many hours in this save, please help :(

Can you provide the save game?

https://www.dropbox.com/s/3gj02dapwyg5s9w/drones3.zip?dl=0

I pushed an update which should fix it

I don't believe it! It works!! THANK YOU SO MUCH!!!
Man, that was fast!! Thank you so much for taking the time!! Love your mod by the way!!