When building unloader with construction bots (and even when connecting it manually to bot-built rails):

The mod Bulk Rail Loader (1.1.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event railloader::on_robot_built_entity (ID 14)
railloader/ghostconnections.lua:20: bad argument #1 of 2 to 'pairs' (table expected, got nil)
stack traceback:
[C]: in function 'pairs'
railloader/ghostconnections.lua:20: in function 'get_connections'
railloader/control.lua:158: in function 'create_entities'
railloader/control.lua:201: in function <railloader/control.lua:194>
(...tail calls...)

I can confirm this issue when using Cut/Paste to build/move unloader stations with bots.
As a workaround until the mod is updated I downgraded to version 1.0.7 and modified the info file to make it support Factorio 1.1. That seems to be working for me without issue so far.

Just received the same crash. It worked when manually placing the loader/unloader.

The mod Bulk Rail Loader (1.1.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event railloader::on_robot_built_entity (ID 14)
railloader/ghostconnections.lua:20: bad argument #1 of 2 to 'pairs' (table expected, got nil)
stack traceback:
[C]: in function 'pairs'
railloader/ghostconnections.lua:20: in function 'get_connections'
railloader/control.lua:158: in function 'create_entities'
railloader/control.lua:201: in function <railloader/control.lua:194>
(...tail calls...)

I have the same problem.

Should be fixed now in v1.1.2.