So I'm currently running off 1.7.10 version of Minecraft and Forge. It seems that .zip files crash my game whenever I copy them to the mods folder, however. I've attempted all sorts of things including extracting them, deleting all of my other mods and other things. What usually happens is that I start up my game, it launches, then comes up with a crash report telling me that the mod I'm trying to install is 'errored'. .jar files work just fine. The mod I'm currently trying to install is the Superheroes Unlimited mod. I also tried to install Mo' Creatures a while back but that never worked either.
Any help or suggestions would be greatly appreciated, thank you.