I've noticed there have been a few people sharing .package files from SimPE extraction. This is not good; they cause issues in the games they get installed into.
Body Shop makes the packaging process take a bit longer, but it means it that all the necessary data is embedded with the shared Sim.
This tutorial shows how to package a sim that is born in game & how to correctly package it, as well as how to include its custom content should you wish to.
( Extracting Sims to Share that Wont Break GamesCollapse )