For some reason, without changing anything (as far as I know), the game simply would not run. Other packs will run on the same FTB Launcher.

Log: http://paste.feed-the-beast.com/view/raw/f0d848e4

Loading the ModularSystems furnace seems to be what's causing the crash. Try re-installing the pack and if that doesn't work delete the folder its stored in and do a fresh install of the pack. Make sure to back up any worlds before deleting anything if your have any.

Force updating still crashed (Log: http://paste.feed-the-beast.com/view/raw/7b65c4eb). Then I deleted the folder (backing up my world) and it loaded up. But when I started my world I crashed and got this log: http://paste.feed-the-beast.com/view/raw/169f72d4

thats a hqm crash, you'll need to delete the hqm file in the world folder to fix it. But doing that will reset your questbook progress

Ok so game loads, world loads but HQM Questing is disabled and I am not allowed to use the command to re-enable it. (Log: http://paste.feed-the-beast.com/view/raw/157e6b7a)

Click Open To Lan and enable cheats then you can run the comment

Ok questing is enabled but hardcore mode was enabled as well and I don't know how to turn it off

You have to delete the file again and run /hqm quest then.