I have found a solution to the problem where linux gets stuck keys while playing minecraft. This bug is from vanilla, but I am rewriting a tutorial for the FTB launcher.
If you are interested you can find the original tutorial here:
http://www.minecraftforum.net/topic/134703-linux-stuck-keys-solution/
Follow these steps to resolve the issue:
1: Backup the saves of whatever modpack you are fixing. MAKE SURE YOUR BACKUP IS NOT SAVED IN THE FTB INSTALL DIRECTORY! To backup your saves Open the folder that FTB installs all of it's files into. If you don't know where this is then run FTB Launcher and select the "OPTIONS" tab. It will show you where you have it set to install where it says "Install folder...".
2: Enter the modpack folder you are fixing.
3: Enter the "Minecraft" folder.
4: Copy the "saves" and "config" folders, and paste them to your desktop.
2: Download the latest version of Lightweight Java Game Library(LWJGL) from here:
http://sourceforge.net/projects/java-game-lib/files/Official Releases/
If you are going to compile from source you want the lwjgl-source-2.8.4.zip file. Otherwise download the lwjgl-2.8.4.zip.
3: Unzip the LWJGL to the desktop, or whereever is convient for you.
4: Open the FTB install folder.
5: Enter the folder of the modpack you wish to fix.
6: Enter the "minecraft" folder.
7: Enter the "bin" folder.
8: Copy:
"jinput.jar"
"lwjgl.jar"
"lwjgl_util.jar"
from the lwjg-2.8.4 folder you just downloaded and unzipped.
9: Paste the files into the "Bin" folder you have open, and select "Overwrite" when prompted.
10: Enter "natives" within your FTB install folder.
11: Enter "native" within your lwjg-2.8.4 folder.
12: Copy:
"libjinput-linux64.so"
"liblwjgl64.so"
"libopenal64.so"
"libjinput-linux.so"
"liblwjgl.so"
"libopenal.so"
from the lwjg-2.8.4 folder.
13: Past the files into the "natives" folder within your FTB install folder, and select "Overwrite" when prompted.
Launch the game to check if it is working properly. If there is some kind of problem that prevents the game from running then launch the FTB laucher, select your modpack, go to the "OPTIONS" tab, and press the "Force Update" button. MAKE SURE YOUR BACKUP IS NOT SAVED IN THE FTB INSTALL DIRECTORY! Launch your modpack and it will reinstall.
After your modpack reinstalls navigate back to the "Minecraft" directory within the FTB install folder. Copy the "saves" and "config" backups that you made, and paste it into the "Minecraft" folder, select "Overwrite" when prompted.
Everything will be reverted to how it previously was.
If you run into any issues post a reply, and I will guide you through a solution to the best of my abilities.
If you are interested you can find the original tutorial here:
http://www.minecraftforum.net/topic/134703-linux-stuck-keys-solution/
Follow these steps to resolve the issue:
1: Backup the saves of whatever modpack you are fixing. MAKE SURE YOUR BACKUP IS NOT SAVED IN THE FTB INSTALL DIRECTORY! To backup your saves Open the folder that FTB installs all of it's files into. If you don't know where this is then run FTB Launcher and select the "OPTIONS" tab. It will show you where you have it set to install where it says "Install folder...".
2: Enter the modpack folder you are fixing.
3: Enter the "Minecraft" folder.
4: Copy the "saves" and "config" folders, and paste them to your desktop.
2: Download the latest version of Lightweight Java Game Library(LWJGL) from here:
http://sourceforge.net/projects/java-game-lib/files/Official Releases/
If you are going to compile from source you want the lwjgl-source-2.8.4.zip file. Otherwise download the lwjgl-2.8.4.zip.
3: Unzip the LWJGL to the desktop, or whereever is convient for you.
4: Open the FTB install folder.
5: Enter the folder of the modpack you wish to fix.
6: Enter the "minecraft" folder.
7: Enter the "bin" folder.
8: Copy:
"jinput.jar"
"lwjgl.jar"
"lwjgl_util.jar"
from the lwjg-2.8.4 folder you just downloaded and unzipped.
9: Paste the files into the "Bin" folder you have open, and select "Overwrite" when prompted.
10: Enter "natives" within your FTB install folder.
11: Enter "native" within your lwjg-2.8.4 folder.
12: Copy:
"libjinput-linux64.so"
"liblwjgl64.so"
"libopenal64.so"
"libjinput-linux.so"
"liblwjgl.so"
"libopenal.so"
from the lwjg-2.8.4 folder.
13: Past the files into the "natives" folder within your FTB install folder, and select "Overwrite" when prompted.
Launch the game to check if it is working properly. If there is some kind of problem that prevents the game from running then launch the FTB laucher, select your modpack, go to the "OPTIONS" tab, and press the "Force Update" button. MAKE SURE YOUR BACKUP IS NOT SAVED IN THE FTB INSTALL DIRECTORY! Launch your modpack and it will reinstall.
After your modpack reinstalls navigate back to the "Minecraft" directory within the FTB install folder. Copy the "saves" and "config" backups that you made, and paste it into the "Minecraft" folder, select "Overwrite" when prompted.
Everything will be reverted to how it previously was.
If you run into any issues post a reply, and I will guide you through a solution to the best of my abilities.
