Safe gameplay

After years of playing TS2 the way EA intended it to be played, I've recently learned that there are several issues which may lead to neighbourhoood and game corruption even if you don't mess around.
So...
This is a list of things you may screw up without really noticing you're doing something wrong.

• Patching your games is really important.
  
  That much I had figured out myself, and I have always used the official patches.
  EA's TS2 official webpage has been down for a while now, but I still keep a copy of those files in case I ever need them again!


• The object.package files may get corrupted, damaging all your game.
  
  It seems that fixing them is usually not very hard, but preventing it is even easier: if you just set those files to read only mode, then no matter what gets screwed at least those files will be safe.
  I found here a list of the locations of all those files, and actually it just took me two minute to gain some peace of mind.


• Don't delete Sims.
  
  Messing around the files and deleting them manually may be harmful. But deleting them using the delete in-game button is also potentially harmful!
  Silly, isn't it?
  But it's said that not all data is properly removed, and problems may start later at any time.


• Don't delete tombstones.
  
  Even if Sims are dead, their files are still there. They remember things, they appear as ghosts and they can even be resurrected, meaning they are technically just as the rest of Sims and should not be deleted.
  Removing a lot which has graves in it, or the death of Sims who have a tombstone in their inventory leads to the same problem.
  Pescado's No unlink on delete mod is essential to avoid tombstone related issues, but still one should never delete them. A community graveyard is definetely a great idea.
  
  
  


• Don't resurrect dead pre-made Sims.
  
  Leave the dead to rest in peace. At least the pre-made ones, since their files have a partial loss of relevant data.
  Resurrecting those who have died during your gameplay seems to be perfectly safe though.


• Saving the game is not as foolproof as it seems.
  
  Don't save with ghosts active on the lot, as the game may remove those tombstones.
  Don't save while a Sim is on the phone, nor when an scenario (date, headmaster, etc.) is active.
  Don't use the save & quit button nor the save & exit button. Instead, save the game and then quit to the neighbourhood or exit the game.


• Don't move an inhabited lot or an owned community lot to the lot bin.
  
  It is specially troublesome if you later move it to another neighbourhood, so better don't!

If you are gonna mess around with custom content or TS2 related tool programs you must be careful with many other issues.
I would suggest to read this comprehensive topic about avoiding corruption. It helped me a  lot!