A couple of things here.
As I understand, you cant be charged for things you did not know about. My experience with a few strata managers , both as owner as committee member, is that if a payment is undetermined initially who is to pay, the strata manager say to the lot owner, the OC will engage the contractor and pay for the work. If it is deemed to be owner responsibility the OC will bill you.
Did you ask for your car park space to be swept? if the OC instructed the cleaner to sweep your car space, then its an OC expenses
Same for your court yard
I think it follows a legal construct where you cant be charged for something you were not aware of or agreed to.
Secondly, any such charges cannot be added to your levy register. Its called a levy register for a reason.
The OC cannot charge you interest if you do not pay the the bill (whether it is legitimate or not).
The OC cannot pay off this debt before paying your levies. The only recourse for the OC to recover such a debt is to take it to a small claims court.
The OC cannot make you unfinancial for the purposes of voting at meetings if you do not pay this debt. Schedule 1 part 4 division 1 23(8) speaks only of contributions, which is the act means levies
Take the stance that I have outlined above. Do not pay the amounts to the OC and then let them take it to NCAT (rather than you paying the filing fee). Its up to the OC to prove that the charges are justified.