Page 88, in A Time of War, describes how to buy additional XPs by taking on negative trait points. The max amount of additional XPs allowed to be bought is described with this sentence: "The maximum number of XPs that can be gained using this method is equal to 10 percent of the XPs originally allotted to the characters design, ..."
My RPG group finds the above quote ambiguous; because, we can think of two meanings for it, which will be illustrated with two examples applied to the same case: net example and total example.
Case: we are creating a character with a starting allotment of 5,000 XPs, and 10% of 5,000 is 500.
Total example: a player can only take up to -5 trait points (from negative traits) to obtain 500 additional XPs awarded to the XP pool, and the amount of positive trait points the player takes is irrelevant to this.
Net example: a player may take more than -5 trait points (in negative traits) to obtain a net of 500 additional XPs, provided they are off set by more positive trait points. So, if a player were to buy 5 trait points worth of positive traits (subtracting 500 XP from the XP pool) and -5 trait points of negative traits (adding 500XP to the XP pool [for a net of zero XPs gained]), then said character would be allowed to purchase an additional -5 trait points to gain another 500 XPs to the XP pool. In sum, the player has acquired 5 trait points and -10 trait points; this nets to 500 XPs awarded to the XP pool.
My RPG group cannot come to an agreement on whether the total or net reading is correct. Thus, we cannot get our game started, please help.