Do NOT put the battlesize over 200 (putting it on 100 or less will probably help a lot if having performance issues or CTDs). Do NOT put Ragdolls and Corpses to 'unlimited' (40 corpses and 10 ragdolls should be perfectly enough). No need to set the max framerate on anything higher than 70-80 (the human eye can only see 60 fps at best, so.) Make sure the Edit Mode is NOT activated while actively playing the game. Make sure 'Load Textures on Demand' and 'Force Single Threading' are checked in the advanced configuration settings. Go to the rgl_config.txt file (inside Mount&Blade Warband folder in My Documents) and change render_buffer_size to 500 (this one is really important). To all people experiencing performance issues and CTDs, hope these tips help (mostly a mix of Kinsume's and Mamluke's advices):

Join them or establish your own kingdom, and become king of all Europe. More than 40 factions wage war against each other in order to achieve domination and power. Europe 1200 is a historically accurate Mount & Blade mod that, as the name says, takes place in Europe, in the year AD 1200.

Warband load textures on demand