So, it is happening to all of the Mod-Packs you have tried on The Twitch-App? Weird?
The reason i asked for a log file is so, we as a community could look it over and see what is causing the crashes. When you run Minecraft and it crashes there is a file called, "crash-*-*-*_*.*.*-client.txt" The Asterisks donate the Year,Month,Day & time the crash happened.
That text file will have the crash report in it. We use that to find out what is causing the crash and try and fix the problem so, it does not happen again. If, you could please post a link to that file so, we can see what is happening. Without it we can't figure out what is wrong.