I am posting this for both mods and not sure if this is something that can be resolved (or resolved easily).

I downloaded a bunch of mods at one time to go through and test out that include Advanced Tanks and Tankwerkz Ltd. On game relaunch I got an error message when loading prototypes as follows:

Error while loading item prototype "flame-tank"
(item-with-entity-data): Prototype "flame-tank" registered twice
Modifications: tankwerkz

Clicking the OK button closes the game.

Deleting either one of these mods resolves the conflict.

Yea thats because both mods use the same "ID" for the flame tank. The only thing i can do is prefix every item/entity this would require a migration script for people already running the mod. I will look into this.

The mod has been fixed to solve any conflicts.