Have experience with many firewall, routers. Here is a HOW TO for quick port forwarding:
1. Create a new custom service...
Main Menu > Security > Custom Service > Add a New Custom Service
2. Give it a name, select the link type (TCP, UDP, BOTH (TCP+UDP), or others
3. Select Multiple Ports. LEAVE SOURCE PORTS BLANK.
4. Enter the source WAN port numbers separated by a comma if using multiple ports into the DESTINATION PORTS
5. Click SAVE
7. Create a new firewall rule
Main Menu > Security > Firewall Rules > Add New IPv4 Firewall Rule
8. From Zone - Insecure WAN
9. To Zone - Secure LAN
10. Service (select the name of your created custom service)
11. Change Action to Always Allow
12. Source = ANY
13. Log = Never
14. Internal IP Address = (IP address of server/pc/device you are trying to forward to)
15. Click SAVE
DONE - Quick and Dirty