While placing loader on Vulcanus got this error. Note other placements of loaders and unloaders on the planet worked okay so I'm not yet sure what conditions caused this placement to break. Trying shifting up/down/left right one tile next.

Error while running event railloader2::on_built_entity (ID 6)
LuaEntity doesn't contain key circuit_connection_definitions.
stack traceback:
[C]: in function 'index'
__railloader2/ghostconnections.lua:21: in function 'get_connections'
railloader2/control.lua:158: in function 'create_entities'
railloader2/control.lua:203: in function <railloader2/control.lua:196>
(...tail calls...)

Agree.
I have this problem too.

https://mods.factorio.com/mod/train-loader has a working version of this mod made from scratch for 2.0. I don't have much time recently to work on this mod as it is much more complex than the others I have worked on and is not a high priority. I will eventually get time to work on it and hope to bring it up to full working order but I have no time frame for when that will be

https://mods.factorio.com/mod/train-loader It's loader only ot unload to?

https://mods.factorio.com/mod/train-loader It's loader only ot unload to?
It will unload too AFAIK, it was meant to be a replacement for the original mod I updated. Since this replacement exists I have focused on other mods and other projects. When I have more time I will come back to working on this mod again but I do not know when that will be.