Cobracon

Hello, This is my first post and I apologize in advance if I have posted the question in the wrong place, or overlooked something obvious. I am a lowly Dad trying to help a kid I am not experienced in Minecraft, so sorry for my ignorance. I have installed Minecraft Launcher 1.5.3 on Ubuntu 12.04 LTS. Then I installed Forge and was using Release 1.7.10-Forge 10.13.0.1180 with Pixelmon-1.7.10-3.2.5-universal and during this time everything worked fine. Then I downloaded and tried to install orespawn164v19 which required forge-1.6.4-9.11.1.965-installer. I successfully installed the forge-1.6.4-9.11.1.965-installer. But with both mods in the mods folder upon loading the program crashed. I found that if I take run orespawn by itself using 1.6.4.... it works fine. If I use pixelmon using 1.7.10.... it works fine. But both together crash. As orespawn came before 1.7.10, and I can't use pixelmon without 1.7.10 so I can't use a older version of 1.6.4.... with pixelmon in the folder. Can I successfully just create a new folder, inside the mods folder, and swap in and out whichever mod I am not using at the time, or will I loose data? How can these both co-exist in a practical way? The FAQ told me to include the log. I hope I attached the correct one. Thanks in advance. [19:44:17] [main/INFO]: Setting user: p3rcy_j4ck50n [19:44:19] [Client thread/INFO]: LWJGL Version: 2.9.1 [19:44:19] [Client thread/ERROR]: Couldn't initialize twitch stream [19:44:26] [Client thread/INFO]: Reloading ResourceManager: Default, FMLFileResourcePack:Forge Mod Loader, FMLFileResourcePack:Minecraft Forge, FMLFileResourcePack:OreSpawn, FMLFileResourcePack:Pixelmon