The problem is that spells aren't learned at a force anymore. So what force of magical lodge is required to learn a spell in fourth edition?

RAW doesn't state, just "a lodge" so rating 1 would cut it.

In my hopinion lodge should be a place of power tied to a magician or group of magicians that grants bonuses to magical activity that takes place inside, I meen why should my ability to learn be tied to a place? I can untherstand the need of a lodge for ritual sorcery but learning a spell or improving a skill? Come on, its burdening the magician (forcing him/her to "make roots" in a place) without any logical reason.

Lodges only take a couple hours to setup, and you can take them down almost instantly.

I think I've missed the part about taking them down, any hint on where to look?

And yeah I forgot to mention that I still dislike the notion of needing a lodge to improve the skills.

It actually makes a lot of sense. Every RL tradition I know of takes GREAT care to create a clean safe space when doing anything like adding to or editing there person. Also it you need ways to hurt PCs to tell good stories.

I don't know, personally I require characters to have access to a target range to improve there shooting and sparing partners to improve hand-to-hand skills, so having access to their libary of books, charms, ect that fits with their style of magic makes sense to me if someone wishes to improve her magical skills.

So, you pick up the physical materials and pack them into moving boxes like the rest of your furniture. The ritual is to set them up, not take them down.