Commission schedule keeps breaking

Here's one of many schedules we have in NS:
Commission on: quota (ASA amount)
per: Period Quarterly (fiscal year)
Eligible amount: collections
calculation scale: linear
rate: percentage
inventory commission base: sales amount
manager schedule: no
inactive:no
___
Commission total
0% for 0% of quota
10% for 100% of quota

So I had this exact schedule set up at the beginning of the year, and it wasn't working properly (while I had similar schedules working only difference was percentage). Basically it was only calculating a small amount on a few of the SO's, and I could get no logical reasoning out of the amount NS wanted to pay, like 1% or the last SO's of the month, nothing (ie someone should have received $25k, instead got like $216). So I recalced the schedule twice in 2 different ways to try to get it to work, and still nothing.