Landships II

Although I'm not a modeller, I'm currently quite engaged in gathering detailed information about WWI weaponry, because I'm involved in coding a WWI mod for a computer game. In doing so, I checked several existing WWI computer games (no reliable sources, I know), read specialist literature dealing with the Great War, and I finally stumbled upon this (very informative) site.

Now, my problem is the following: I've got a German copy of a Russian WWI computer game that uses the so-called "Enigma/Blitzkrieg engine". The game is developed by the Russian company "Dark Fox" and the English version is simply titled "World War I". It has some great game models, though it heavily lacks of realism (e.g. you have A7Vs in 1914). Therefore, I decided to make some kind of a "realism mod" that has correct unit stats, correct unit nomenclature, etc. Though the game models are obviously based on existing WWI weaponry (even on exotic ones, e.g. the rarely known "Lance-mine Gatard"), the nomenclature is often pure fantasy, so it's hard to figure out what exact vehicles the Russian programmers had in mind. Unfortunately, there is no chance to contact them.

For example, the game has a mysterious German/Austro-Hungarian trench mortar that is called "180 mm GRANATWERFER" that looks similar to a "Böhler 24-cm-Minenwerfer M 16/17". The only thing I found in literature is a well-known picture of a "18-cm-Gaswerfer" (gas projector) that you maybe already know (see below).

I'm wondering if someone on this forum has ever heard of a German 180 mm trench mortar? I only know the Germans had a 170 mm mortar made by Rheinmetall, but that's a separate unit in the game.
Any information on the German 18 cm gas projector may be helpful, too.

Thanks in advance
Beorn