I don't know your exact circumstances and I want to try and be non-judgemental, but are you kidding me?? First of all, you're saying you haven't been making your mortgage payments on time, your husband has a BK so he has trouble with money as well, and you want to buy another home??
If you're in the percentage of people who are upset their home's value is down and want to take advantage of lower prices and dump a bad investment, then shame on you. You knew very well what you were signing and you should live up to your obligations.
If you just can't afford your payments and have the idea of downsizing to something more affordable, then you need to do a better job of controlling your finances and learning how to manage money. Otherwise what's to say you won't wind up in the same predicament getting another home?
Either way, it's no surprise to me that any lender willing to even consider giving you money is requiring a sizeable down payment on your part. My guess is that you don't have 20% just sitting around.
Now I'm giving you the benefit of the doubt in believing you're not a shady character just looking to take advantage of the system, so here is my advice: put a hold on your plans to buy another home, work oin improving your credit and learning how to save money, and try to apply for a mortgage when you have a good handle on these things. Owning a home is a privelege, not a right. The more your average everyday person understands this, the closer we'll be to getting out of this whole real estate mess