Couple of things wrong with your install of FTB.
1) Update your java. Java 7 update 21 is the latest. Find the
link here.
2) Added URL to classpath: file:/C:/Users/Steven/AppData/Local/Microsoft/Windows/Temporary%20Internet%20Files/Content.IE5/6EF7904V/Direwolf20/instMods/MinecraftForge.zip
You do not want to use the temporary internet files folder to install FTB. Backup your saves. Delete the FTB folders inside the Temporary Internet Files folders and the launcher from in there. Download the launcher and put it in a folder on your desktop and run it from there. These tips courtesy of this
guide.
3) Make sure GUI Api is in your core mods folder. And which version of Mo'Creatures are you using? The ported version? I've seen in a thread that there is an actual 1.4.6(7) version that worked for a user with problems.
