F'14, bugs or features?

[Volcano Man]

1) When the army of the North arrives it's loaded on trains allright, which seems to indicate that it should have a separate rail capacity. But from that turn until they are unloaded all the standard capacity is absorbed too. Is this intentional?

Correct, it is intentional. See page ~79 of the notes.

In a nut shell, both sides still had nearly their entire rail capacity / rolling stock occupied with mobilization issues during the campaign. These units that arrive by rail are scheduled as part of the mobilization. I don't want too much rail capacity because once these scheduled transported units were dropped off, the trains left immediately and carried on with the other scheduled tasks; they did not sit around waiting to transport other units.

So, rail capacity essentially represents the "extra" amount of rail transport that is specifically dedicated support, which was very little. No telling what I wrote on page 79 of the notes (it is two pages), so you should still read that for more detailed information. ;)

2) I tried to destroy a wall at Givet (SE hexside) I was asked if I wanted to destroy the bridge instead. I tried a few key combinations while making the menu choice to destroy wall, but to no avail.

This is a bug that is fixed in the next version (1.02).

Hope that helps.