Well I've encountered a bit of a snag comming up in my adventure. The players are stranded on a backwater feudal world that doesn't speak Low Gothic. Using an idea from Guant's Ghosts, I can probably say that some root words come from Old Gothic, but for the most part, the language/s is/are different. I took a peak in my books and there are no rules for learning new languages. Sure I could probably explain it through role-play and with the swish of my players collective penicls, but if there are any suggestions to make it more difficult than just saying "Ok, you gain the skill speak language(x)", I'd be most appreciative.

Have them make Perception checks (hearing) when a native is speaking to them. Only the one with the highest score makes the check with a +10 for each additional PC whose also listening and helping decipher what's being said and another +10 if they know High Gothic. Once the check is made, have the native say what the PC's think the native said based on their success or failures. The more they fail/succeed, the more they misinterpret/understand but make sure you don't tell them which parts of their interpretation that didn't understand so well and which parts they did... that can lead to some amusing situations ;-).

The first time they hear a native speak, the difficulty will be at a -60 (not including bonuses for knowing High Gothic, having help, or having good hearing). Each week that goes by that they listen to the natives, add +10 to the modifier (the second week would be -50, the third -40, etc). Each time they succeed in their perception check, they also gain a +10 to the difficulty. Once they reach +60 (not including bonuses for knowing High Gothic, having good hearing, or help) difficulty, they can communicate with the natives without having to roll any longer.

When speaking, they must make a Intelligence test at the same difficulty as their Perception test. This is, again, modified by having good hearing, help from others, and knowing High Gothic. The natives comprehension of what they say will be based on the degree of success or failure following the same guidelines for their comprehension of the speaker.

I can only imagine that Lore (Cryptography) would help immensely at this task. Translating "on the fly" a language you have never encountered before, even if it's in the same language family as your own, is freaking tough. If you don't believe me, try going to Germany without any German lessons and see how well you get on (admittedly, a good number of them speak English, but not so many as in Norway).

You might use the above system, or make Cryptography the core Skill (in which case it's not going to be something many characters can do, which is realistic but might be detrimental to the game). Either way, just assume that the base Skill or Characteristic value, unmodified (except, perhaps, by supporting Skills, something like as given above), is the proportion of the amount of "text" the character understands. Thus, if you've got an Adept with Lore (Cryptography) at 48 and he speaks High Gothic (58%), assume around 60% of what is said to him is understood by him. Thus, the natives might start going on:

"Wonjo, human. I am excellent, jurango. You agents are with the man with the face, and you walking with me purang the Elder, no question."

Translated properly, the phrase might be:

"Hello, sir. My name is Jurango, your excellency. As you are come from the Inquisition ('Emperor's Men'), I must take you to the Elder Purang immediately."

This is a quick, "no-rolls" way of handling it. The native's comprehension can be handled similarly.

And, fo course, ultimately the pcs will understand just as much as you need them to understand for the game. Even if they don't have the necessary skills, give them appropraite checks to realize that the monster lives in mountain X and can only be approached through villages Y and Z.

Naration should never have to bow to mechanics if you do things correctly.