Help with modpack, some players have broken textures or crash on startup?

[turkfalso]

Yep title says it all, when it launches up, the players will  have no item textures, even mods and vanilla items.  

also some people crash on the mojang screen when launching up. 

Anyone know why this happening, i really need this to work better please!

Here is modpack: http://www.technicpack.net/modpack/details/2epicpandas-dayz-ganzurino.291733

[turkfalso]

anyone???