i think you are way too qualified for an assistant postion, which basically involves cleaning, and setting up stuff. but childcare centres are desperate for staff (due to crappy wages, conditions, sickness etc) so i would bet that you would get the job. i reckon you will find it unfulfilling, considering you are used to taking charge and running a classroom. you could even get a group leaders position if you really wanted to with that qualification, you would probably have to do some sort of study though.
it wont look bad on your resume, because you could outline in an interview things that you didnt like about an ABC centre (or other centre) and how you could turn that into a positive in the new centre... etc.