Okay, first off... you need more google-fu, because there's been several threads on this topic. However, in the interests of education, I shall reiterate my previous statement which I still feel to be accurate...
There's a HUGE difference between 'make a custom mod pack' and 'edit a current mod pack or throw a bunch of mods together that I play just for myself'.
To want to make a custom mod pack, you'll want to go through this checklist:
- You want to play with a selection of mods that isn't just 'x mod pack' with a couple of mods included or removed
- You want to widely distribute this so that everyone can play with it, not just yourself or even you and your close friends on a private server
- You want to go through the effort of obtaining permissions for every single mod in the mod pack
- Which means all of the mod authors have to be willing to give you permission, which means you can't include mods which have mod authors that don't want their mods in mod packs (like TC3 and Ars Magika)
- You are willing to maintain the mod pack after release. This means:
- Editing config files to be most compatible for everyone and present a reasonablly balanced gameplay for your users
- Checking all of the mods at least weekly to make sure you get important updates for your users
- Collect bug reports from users and either update config or mod versions to fix them, or report them to mod authors in the proper venue
- Willing to listen to user feedback to tweak the settings on your mod pack
If you do not have 'yes' as the answer to
every line in that checklist, you probably don't want to make a custom mod pack, you just want either a config pack or something to play around for yourself and/or your close circle of buddies.
If you want something to play yourself, I'd strongly suggest
MultiMC. You can import FTB mod packs, then edit them to your liking. You can even set up multiple instances with different mod configurations.