Your log doesn't show the error downloading issue.
You did not complete the troubleshooting guide correctly.
You need to remove all of those other Java versions you have.
You should only have Java 7, u45. Presently you may as well have every version of Java except that one.
Code:
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.6.0_31 sorted as: 1.6.0_31 32 Bit Java at : C:\Program Files (x86)\Java\jre6\bin\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.6.0_07 sorted as: 1.6.0_7 32 Bit Java at : C:\Program Files (x86)\Java\jre1.6.0_07\bin\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.7.0_25 sorted as: 1.7.0_25 32 Bit Java at : C:\Program Files (x86)\Java\jre7\bin\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.7.0_07 sorted as: 1.7.0_7 64 Bit Java at : C:\Program Files\Java\jre7\bin\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.7.0_07 sorted as: 1.7.0_7 64 Bit Java at : C:\Windows\system32\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:137: Java Version: 1.7.0_25 sorted as: 1.7.0_25 32 Bit Java at : C:\Windows\SysWOW64\java.exe
[11:25:35] [INFO] JavaFinder.parseWinJavaVersion:159: FTB Launcher Prefers: Java Version: 1.7.0_07 sorted as: 1.7.0_7 64 Bit Java at : C:\Program Files\Java\jre7\bin\java.exe