CGN DHCP will not give out IP addresses

I actually need “Port Address Translation” because I’m an ISP with limited amount of public IP addresses so I was thinking about 30-100 customers behind every public IP.
I’m going to have the 1040 connected in/out next to the core router Huawei NE40e-M2K that is going to act as DHCP as well initially.
When you say routed hop, do you mean a private link-net between inside and outside ports to core and then ip routes?
I’m having a really hard time understanding the CGN equipment and the communication logic between A10 and core.
Is it LSN that would equal “Port Address Translation”? (see attached picture)