problem with port forwarding (bug virtual box?) and other

[sr.upload@yahoo.com.br]

Hello, I'm Brazilian and do not speak English so excuse my bad english. It was translated google.

summary

Real machine (host) Seven.
Virtual machine (guest) XP.
Virtual box 4.2.10 r84104

1) Problem in port forwarding for UDP using the XP virtual machine (Guest XP) to run eMule. And again and again problem in TCP redirection for virtual machine using XP (Guest XP) to run eMule.
2) Security of the real machine (host) x virtual (guest) x x network NAT Network Bridge.

Detailing the problem

1) I am virtualizing Windows XP to run a program P2P eMule. However, I'm in trouble as the ID HIGH and LOW ID in the program.

I do port forwarding in virtualbox, but still eMule does not work right. It seems crazy, strange, weird or buggy (no bug). For he sometimes gets high on ED2K network ID and ID never gets high in KAD network. The doors are all open, so when the guest host.

Using the GRC site (online portscan) TCP port (it seems I did the redirect correctly) appears open. UDP but I do not know and do not know a site for testing. But anyway, as I know the KAD network protocol uses UDP, I think that door is standing problem for not having ID HIGH (never got high ID in network KAD) eMule on the virtual machine (Guest = XP)

2) Another question: I use a virtualized machine eMule (guest) in order to protect the real machine (host). For this use NAT mode. I read on the internet that this method is safe and protects the actual machine (host). This type of network (host-guest) NAT is even safe? Or so the bridge would also be safe? Remembering that my goal is to isolate the real machine to virtual machine.

I'll be grateful if you can help me.