I installed an external capacitor on the battery module to allow the proper reset sequence into the core module.
Ok, now I buyed a LAN module which does not have the output connections, so I solved the problem as in the image.
Thank to the big dimension of the ethernet socket, there is a lot of space to mount a 4,7uF capacitor.
Note : that cap was what I already have in my lab.
Now everything is ok, but the question is: do you plan to solve this issue in a future release ?
For a massive (industrial) use of your module, a workaround must be done for every module, and this is not acceptable...