Petr,
I see you have four different topics going at one time. And all are active.
my best advice is not to try NOT solving all four at the same time. This becomes very confusing for both of us.
Pick one to solve. Maybe the DNS & DHCP, trouble first since that seems like the most important to me.
Is the IPFire system hosted at Amazon? If it is, please let the other volunteers know.
Also, please post your images / screenshots on the IPFire site and not a remote site. The Upload button will help grab your pictures.