Bug Description

While making some tests with the mekanism laser (and the tractor beam from the same mod) my game crashed. Restarting the game now keeps crashing immediately before I can undo it. So here is what I did in detail:

• first I placed a laser pointing at a tractor beam pointing at nothing. After testing how these two items work and whether the laser is harmful and whether it breaks blocks (tested with a gravel block), I removed both - the laser and the tractor beam
• For another test I then again placed the laser somewhere else without connecting it to electric power. However I didnt keep in mind that the laser has an internal power storage. So it started shooting. My thought was "oh damned" and I turned around to see where it was shooting: It was aiming at a block from the "advanced generators" pack. More specifically a block from the gasturbine. I cant exactly tell which block because at the moment I don't want to start the game due to the fractureiser-issue (even though I checked that i am not yet infected as it seems). I think it was a block for outputting electricity. Will validate that once it's safe again to log in and I found out how fall back to an earlier gamestate via the backup function.
  Anyway ... before i could remove the laser the game crashed. Probably in the moment, where the block it was aiming at broke. I tried restarting it two more times but even before I get to the firstperson-view of my character it crashes again.

Maybe something related: I noticed a strange behaviour of "advanced generators"-blocks before. Usually you place the various component-blocks (i.e. gasturbine-mainblock, turbines, inputs, outputs) together and they autoconnect, forming the complete generator. This is also indicated by a thick black border around the edges of the whole blocksetup.
However if you pickup a block by shift-right-clicking it, move it away and place it again somewhere else, then the block still seems to be connected to the generator-setup (kind of a magic wireless connection). I didnt test if the generator would still work that way, but at least I get the GUI of the whole generator when right clicking the single, seperated block.

I hope this description is not too confusing and long.

Did this behavior use to work in the previous version?

Steps to Reproduce (for bugs)

Logs

• Client/Server Log:
• Crash Log:I hope this is the right crashlog: https://pastebin.com/cC9RNfsK

Client Information

• Modpack Version:
• Java Version:
• Launcher Used:
• Memory Allocated:
• Server/LAN/Single Player:
• Optifine Installed:
• Shaders Enabled:

World Information

• Modpack Version world created in:
• Additional Content Installed:No

Oh. A quick hint on how to import a backup would be nice. Couldn't find an option for that in CurseForge. Is it done from ingame-mainmenu? I found backups in the ".../SevTech Ages Of The Sky/[Worldname]/backups/"-folder. But I never imported one and can't try it at the moment. A quick hint on how to do it would make things easier for me once starting curseforge/SevTech is safe again, but if you are busy don't waste time on it. I guess I will figure out.

You might be able resolve this using Forge's automatic removal of crashing tile entities feature:

1. With the game shutdown, open ./config/forge.cfg
2. Make the following change

     # Set this to true to remove any TileEntity that throws an error in its update method instead of closing the server and reporting a crash log. BE WARNED THIS COULD SCREW UP EVERYTHING USE SPARINGLY WE ARE NOT RESPONSIBLE FOR DAMAGES.
-    B:removeErroringTileEntities=false
+    B:removeErroringTileEntities=true

3. Start the game, load your world and remove any blocks that were affected.
4. Close the game again, and revert the changes to forge.cfg

If that doesn't work, then restoring backups is a manual process;

1. Move the existing world folder somewhere else, e.g. ./saves/WORLDNAME to ./saves-old/WORLDNAME
2. Create a new folder with the same name as WORLDNAME in ./saves
3. Navigate to ./backups/WORLDNAME and extract the most recent (working) backup to: ./saves/WORLDNAME

Update: The automatic blockremoval option by changing ./config/forge.cfg did not work. The game still crashed. The following message was shown in the minecraft-launcher:
"The game crashed whilst ticking block entity
Error: java.lang.RuntimeException: Attempt to get TE net.bdew.generators.modules.fluidOutputSelect.TileFluidOutputSelect on a mismatched block minecraft:air at BlockPos{x=530, y=66, z=455}"

Will try restoring the backup.

Restoring worked. So I can give more info. Here is a screenshot of where the laser was pointing to. The laser itself is not show of course due to backuprestoration.

The laser was pointing from right to left at the block with the purple-framed output ("forge energy emitter"). In the same row (from right to left) are the following blocks: gas turbine controller, fluid intake valve and - after a gap of air - a fluid output valve.

The fact that the last crash-message was about "net.bdew.generators.modules.fluidOutputSelect.TileFluidOutputSelect" might indicate that after trying to start the game for 3-4 times (didnt count it) each time a block was removed and the server crashed. So maybe it would have run again if it tried again again until all blocks in the row would have been deleted.

Let me know if you need further info.