BEND:
Represents bodily flexibility; the ability to move yourself. Whenever you try to move quietly, climb a complicated surface or leap a large distance, this is the skill that will be tested. Contrasts with Perform, which can be used to represent manual dexterity; dancers and assassins want high scores in both. Contributes to your Melee Defence in combat (bending with the punches makes them hurt less!) and increases your party's Enchant Self pool.
FORCE:
Represents strength; the ability to move other things with your body. Whenever you need to push, lift or carry something, roll vs. this. Also useful for intimidation. Contributes to your Melee Attack Power in combat and raises the chance your party will counterattack when ambushed.
RESIST:
Your stubborness, resilience and ability to survive. Whenever you need to maintain an action for a long time, withstand extreme conditions or sustain torture, this is what you'll need. Contributes to your Maximum HP and increases the party's maximum encumberance.
CONCENTRATE:
The ability to withstand mental exhaustion and to shut out distraction. Characters who hope to cast complicated spells in combat need a high score here. Contributes to your Magic Attack Power and improves the party's chances of solving a puzzle by themselves.
IMAGINE:
Your creativity. Graydnmuch is full of artists, authors, poets and musicians; many characters will have fostered an active imagination thanks to a burgeoning art scene, and if that doesn't grab you, it also increases your Maximum MP and the party's Enchant Item pool.
UNDERSTAND:
Represents comprehension of the world. Any number of scientific and technical skill checks call on this one (and you'll be using the nascent internet quite a lot.) Also contributes to your Magic Defence score and allows the party to equip the weird items they'll surely discover in various wraeums and secret underground test sites.
APPEAL:
The ability to make other people see things your way. Encompasses argument, misleading people, storytelling and functions as a kind of "looks" ability, all in one. A good uni lecturer would need both Understanding and Appeal. Contributes to the party's Enchant Other pool and increases your Ranged Defence (this is the weakest link of the nine, but somewhat models you making people unsure of wanting to attack you? Tenuous, I know...)
EMBRACE:
Represents the ease with which you enjoy social activity. A high Embrace score makes you approachable and easy to indulge, and you in turn find it easy to indulge others and their art. Contrasts with appeal by being more of a fitting-in stat; an unsociable person with a great sales pitch could have high Appeal and low Embrace. Having a high score here increases your Maximum Stamina and makes the party luckier when it comes to finding or discovering things.
PERFORM:
This models manual skill and its expression, but also covers diligence and attention to detail: a live musician playing a complicated two-hour set needs perform for both reasons, but a priestess perfoming a long ceremony and a gamer solving a Rubik's cube both benefit from it in more specialized ways. Hitting a target requires perform, so it naturally raises your Ranged Attack Power, as well as the party's presence of mind when it comes to avoiding ambushes.