Gigi CSA keep track of every cent that is paid or not paid. this is how they know that he owes for his other child. if he has an income below a certain threshold, he would have to pay the minimum amount, which would be divided between the two families. if he isn't paying enough to cover both his current liability to you and to the other child, they would pay some to each family, and keep a track of how far he is falling behind. if he has a job now, and he isn't paying properly, they may be able to garnish directly from his wages. they can also force him to do tax returns i believe (if he doesn't, they will reassess his liability to a higher level because he is not meeting his obligations i think)

child suppot only impacts you in the year you receive it. if your ftb is reduced at all due to the assessment (which it shouldn't be - 40 a fn for 26fn is below the income thresholds to impact ftb), at reconcilliation time, the ftb system will calculate exactly what you received from child support (to the cent) and pay ou back any ftba you have had reduced. if he is SUPPOSED to be paying 40 a fn for CS but is only paying 20, and it is impacting your payment, call up FAO, talk to them about entitlement vs disbursment. i won't go into it here, because it is a messy set of calculations and only really relevent if the assessment (which i get is about 1040) is high enough to impact your ftba (around 1350 per fin year). i don't want to confuse you - just keep an eye on it - if your ftb part a goes down, give FAO a call to discuss

in terms of housing department i would check with them what happens if he is not paying his full liability via CSA. i know they look at a percentage of your income and thats what you pay, but if he isn't paying and child support can confirm that, they may reassess on what you're actually getting.