Body Armour provides your character with an extra measure of protection. It is not a normal skill, in that it has no attributes associated with it (and hence no percentage chance for success), it cannot be improved upon (under normal circumstances); it may be 'purchased' more than once, but it may not be purchased or learned after the character creation process is complete. It may not be given out as a 'freebie' by the GM based on the character history.
Body Armour must be purchased when the character is created. It may be purchased as many times as desired, up to the limit listed for the character's race. Each purchase will add one to the 'level' of Body Armour possessed by the character. Note that Body Armour is not related to itself. That is, each level purchased costs the full 50 increase points.
Some races will start with a certain amount of free Body Armour. This will be noted in the race description. This is to reflect the fact that some creatures (a rhinocerous, for example) have particularly tough skin. Simply add this to the amount of Body Armour purchased. Note that the limit listed in some race descriptions does not include this amount; that is, the limit specified is the maximum that may be purchased.
A character's Body Armour is added to the Protection value of whatever armour the character is wearing.
Killer has Body Armour at a level of 1. His armour has a Protection value of 3. Killer now has a combined Protection value of 4(=3+1).
Body Armour also decreases the amount of damage taken by a character who hits an armoured opponent with bare hands (or feet, tail, etc.). Simply reduce the amount of damage the character would otherwise receive by the amount of Body Armour the character has.
As a result of the loss of flexibility incurred by having tougher hide, each level of Body Armour purchased reduces the character's Hand-Eye Coordination by 5. This reduction is done after all Increase Points have been spent (that is, it is the final HEC which is reduced, not the average value, or any point in between), and affects all skills which rely on HEC, as would be expected.