help for separate send and receive

hi ,

i have RB450 and two network .

1- 10.10.10.1/24 Gateway

2- 192.168.0.1/24 Gateway

network 1 connect to ether1 , network 2 connect to ether2

who can i separate send and receive , send on 192.168.0.1 , receive on 10.10.10.1

and use Nat for users 172.16.90.0/24

users use ip range 172.16.90.0/24

http://wiki.mikrotik.com/wiki/Firewall_nat

view the “dstnat” and “redirect to” functions.