DNSSEC & Reversed DNS

I just signed my DNS zone with webmin. Everything went fine, I suppose! ;)

I haven't dealt with this before, thus could you please be kind telling me:

1. There are a lot of new entries in .zone file, at the bottom, after my initial records. Is this alright?
2. If I try to check my zone with http://network-tools.com/nslook it doesn't look standard anymore, you can't see that much of information anymore and basically the only thing is left is information about ns servers. Is this alright?
3. Is this good in general to use DNSSEC?

My other concern is that it's been almost 24 hours since I have setup reversed DNS and as I suppose I have set it up properly, because if I use, host 1.2.3.4 it provides me with proper return. But if I do it with external networks it's not there. So my 4 question is about reversed DNS:

4. how much time does it take for reversed DNS to work? Should I set up anything in firewall, maybe? Or it's default 53 port is all you need as it's DNS, right? Are there other means to check if if my reversed DNS record is working properly? Or having proper return from host command is already a good sign? Should there be any slave zones? I only have one master zone?

Thanks, Ilia