Playing with Py and AFH with AFH for Py mods on 1.1 and I have/had hundreds of valves in my base. So I delayed migrating from 1.1 due to the valve issues, but people on Py Discord suggested this app and that they should migrate so I did and my fears happened and all my valves have gone.

Can you help at all? My valves were primarily the AFH ones (as they were customisable) and not 'vanilla' Py valves. But possibly 'AFH for Py' and not 'vanilla' AFH either.

For other people might stumbling accross this, it is possible.

1. Remove the Advanced Fluid Handling mod and any valve mods from your mods directory.
2. Add the two zips from here mods to your Factorio 2.0 installation.
3. Open your save (that was last saved in 1.1) - make sure all valves are migrated correctly. Save your game
4. Close Factorio.
5. Delete these two mods.
6. Add the latest version of Valves, and the version of advanced fluid handling from the mod portal.
7. Open Factorio again and make sure your valves are still good.

It's still on my TODO list to allow migration if that mod doesn't add the valves back. It's now easily possible again due to new APIs being available.

It looks like with Factorio adding in a valve entity in the experimental version, and causing the save to fail. I tried putting the 2 zips into the mods folder but when launching Saying AFH.Migration.Testing must be a dictionary in proprty tree at ROOT. I know experimental is its own beast, but reverting to factorio to stable and an old version of valves (I had 1.2.1) allowed me to continue playing and saving