Basic offline LAN setup with mapLite

Hi, after a lot of tinkering i have to ask for help.

I have a mapLite and and i want it to work like this.
Raspberry pi webserver connected via cable into the router. The pi has a static ip 192.168.0.100.
Everyone else can connect wireless and recieve a dynamic ip? (i dont care how this works but i dont know the devices that might connect and have no control over them).
Then users can connect to my pi webserver typing 192.168.0.100 in their browser.

I have gotten this to work sometimes, but then all the sudden it fails and i dont know what im doing at all.
I have a different router where this was pretty much plug and play.

I should also mention that i dont need any internet access stuff, this is strictly offline setup.

Sounds easy. If you start with blank config, create bridge with ethernet and wifi, add e.g. 192.168.0.1/24 to it, configure wifi parameters, set up dhcp server on bridge (make sure 192.168.0.100 is not part of pool) and that’s it.

Thanks alot, that worked. Good tips to start with no default config when doing something as simple as this.