Question for Brume 2 setup

Hi All,
I recently bought a new Brume 2 but have challenges to integrate it into my network.

Setup:
ISP Router (needed as Modem and for some IoT devices) → Brume 2 → Private Router & Network
ISP IP: 192.168.2.1 → Brume 2 has 192.168.2.20; Portforwarding for 1194 + Wireguard active
Brume 2: 192.168.2.20 (Gateway & DNS is 192.168.2.1) static IP → LAN Router IP: 192.168.3.1; DDNS active; Portforwarding for 1194 active
Private Router: WAN IP 192.168. 3.2; NAT & DHCP activated

In my private network I have a Syn NAS running, which builds up an OpenVPN connection to another location. So far it was working (without Brume 2). But since I have installed it, it doesn’t work anymore (Problem 1).
While I have setup a Wireguard VPN Server on my Brume 2 and can reach it from outside, I am not able to connect to any other device in my network then (Problem 2).

Thanks for any hints what I have done wrong.

SFGD

Allow Remote Access LAN is what I thing you are looking for.