openttd updated to 1.5.0-beta2

--HG--
branch : openttd

docs/desync.txt

@@ -106,7 +106,7 @@ Table of contents
   The important thing here is: The detection of the Desync is
   only an ultimate failure detection. It does not give any
   indication on when the Desync happened. The Desync may after
-  all have occured long ago, and just did not affect the checksum
+  all have occurred long ago, and just did not affect the checksum
   up to now. The checksum may have matched 10 times or more
   since the Desync happend, and only now the Desync has spiraled
   enough to finally affect the checksum. (There was once a desync
@@ -194,6 +194,7 @@ Table of contents
    - Get the same version of OpenTTD as the original server was running.
    - Uncomment/enable the define 'DEBUG_DUMP_COMMANDS' in
      'src/network/network_func.h'.
+     (DEBUG_FAILED_DUMP_COMMANDS is explained later)
    - Put the 'commands-out.log' into the root save folder, and rename
       it to 'commands.log'.
    - Run 'openttd -D -d desync=3 -g startsavegame.sav'.
@@ -217,6 +218,11 @@ Table of contents
      the last dmp_cmds that reproduces the replay and the first one
      that fails.
 
+  If the replay does not succeed without mismatch, you can check the logs
+  whether there were failed commands. Then you may try to replay with
+  DEBUG_FAILED_DUMP_COMMANDS enabled. If the replay then fails, the
+  command test-run of the failed command modified the game state.
+
   If you have the original 'dmp_cmds_*.sav', you can also compare those
   savegames with your own ones from the replay. You can also comment/disable
   the 'NOT_REACHED' mentioned above, to get another 'dmp_cmds_*.sav' from