It was an FTB Launcher error. I think they corrected the link now.
They haven't. I'm trying the Infinity fix now, will edit in a bit.
EDIT :: So the file it said I needed (MrTJPCore-1.7.10-1.0.7.14.jar) was not in the Infinity pack. I found it
here. If you want instructions on how to make the pack work for the FTB launcher, here goes:
- Download the file from the link above, saving it to your downloads folder (or wherever you have it set to save)
- In the search box in the start menu, type %appdata% and hit enter. This should open up a file browsing window that displays the files located in the file 'Roaming'.
- From there, go to TheLangoliers>minecraft>mods. This folder will have a lot of .jar files in it.
- Copy the download from step one into the mods folder. DO NOT UNPACK IT.
- Launch FTB and play TheLangoliers. If your only issue was this missing file, it should launch perfectly.