Dear community,
The process explained above actually works, just be carefull if you created sub-processes and processes, you can`t just export then import processes and related flows, you also need to export-import all sub-processes related to your processes. If not, sub-flows are not taken into account, and you will obtain underestimated impacts (for me, on a process of car tire I created, it implied a 30% underestimation of environmental impacts, so it can be really really bad for your assessment quality !). OpenLCA software said there was a failure in the calculation though, so just be careful about all that.
Best,
Anne