Alright, I made a custom modpack to play with a few friends, and it works perfectly, both the server and the modpack. That is, until I try using MCPC+. I get countless errors that never showed up before when I try using MCPC+ until it finally just stops (but doesn't crash). Eventually, I can't close it, I actually have to go close the process with task manager. I will post links to the crash logs. Oddly, the forgemodloader log stops at some point, and doesn't record all of the errors, so I copy and pasted what I could from the server client (command prompt). Thanks in advance.
From command prompt: http://pastebin.com/uSsvY2Ut
Server log: http://pastebin.com/LNt4Pxyh
These are the only logs I have, as there is no crash lag since it apparently never actually "crashed".