The Turkish artillery stubbornly refuses to Barrage, in spite of the counter showing two barrages available. The Turks have no Artillery Barrages available in central stocks, and this fact seems to be stopping the gun firing what it does have to hand anyway.
In fact, I noticed with German artillery, the only option ever offered is Reload and Barrage. I have never been offered a pure Barrage option, which would allow me to run down the ammunition carried by individual units, leaving a central reserve of purchased artillery barrages.
How do I identify siege artillery? The icons look identical. Does the S- on some CP units identify siege artillery? If so, what does the L mean?
Does gas work? I saved up my four gas attacks until an important moment, and then launched gas attacks against three important hexes. Not one of those three attacks succeeded.
More worryingly, although stocks of gas were reduced correctly, none of the three artillery units used actually produced a paused display revealing the effect. Now, when you use conventional munitions, you get a paused display identifying factors fired, etc, one field of which says 'no gas effect' ... so I rather expected when gas was fired there would be a similar display. But no.
I have come to the conclusion that gas is useless and a waste of time researching.