[21:17:12] [Server thread/INFO] [fml.ModTracker]: This world was saved with mod ihl version 0.508 and it is now at version 0.509, things may not work well
[21:17:12] [Server thread/INFO] [FML]: Injecting existing block and item data into this server instance
[21:17:12] [Server thread/INFO] [FML]: Found a missing id from the world ihl:blockFluidRubberTreeSap
[21:17:12] [Server thread/INFO] [FML]: Found a missing id from the world ihl:ic2cell_fluidRubberTreeSap
[21:17:12] [Server thread/INFO] [FML]: Found a missing id from the world ihl:blockFluidRubberTreeSap
[21:17:12] [Server thread/ERROR] [FML]: There are unidentified mappings in this world - we are going to attempt to process anyway
[21:17:12] [Server thread/ERROR] [FML]: Unidentified block: ihl:blockFluidRubberTreeSap, id 669
[21:17:12] [Server thread/ERROR] [FML]: Unidentified item: ihl:ic2cell_fluidRubberTreeSap, id 4750
[21:17:12] [Server thread/ERROR] [FML]: Unidentified item: ihl:blockFluidRubberTreeSap, id 669
[21:17:15] [Server thread/INFO] [FML]: Applying holder lookups
[21:17:15] [Server thread/INFO] [FML]: Holder lookups applied
[21:17:15] [Server thread/INFO] [FML]: The state engine was in incorrect state SERVER_STARTING and forced into state SERVER_STOPPED. Errors may have been discarded.
[21:17:18] [Client thread/INFO]: Stopping!
so the rubber fluid stuff is no longer important then?