Tried downloading it again, this time in Firefox instead of Chrome. And it downloaded completely this time, and installed without a problem.

Hello. Bought the Grand Campaign 42 DLC, and downloaded the file, but when I try to install it I get a "Failed Self Extraction" error. Tried downloading it again, but same error(Got the other Grand Campaigns aswell, and had no problem installing those). Seems like there might be a problem ...