I managed to somehow stick myself in a wall, and wanted to use Dev/Producer Mode to get out. However, while I can enable cheats ("schnosm " in the options menu) in the normal manner, dev mode (Alt-F12) just seems to play an odd noise and doesn't activate it.

I find it odd, because the Alt-F1-F11 codes work, just not that one. Was it broken intentionally?

I don't know if it got broken intentionally, but I've never got the dev mode to work in the retail edition either (and I've playing that one since 1997). Which is a real pity, because there are some secret rooms in two of the later dungeons which I've no idea how to enter.

Technically it's not broken, but Alt-F12 is mapped by DosBox to "Unlock speed (turbo button)" by default.
To use Alt-F12 in Albion you need to unmap it (in DosBox) or remap some other key combination to Alt-F12 (I never tried either, so don't ask me how).

Or as an alternative you can try the unofficial Windows/Linux port - it should work there. I can't post links, but it's mentions in the thread "Lets play Albion (Linux, native)" for example.

I didn't think of that.

I've changed "Unlock speed" to Ctrl-Alt-F12 in the keymapper and dev mode works now. Thank you very much. :)

Now I'm just no longer sure, if I actually tried using the dev mode while I was still playing the game under DOS, or only after I've moved on to DOSbox. <.<

The command is called "Speedlock" in the keymapper. I don't recall whether that term changed in recent versions of DosBOX or whether I simply called it "unlock speed" because RP1 did. Probably the latter.

In any case, all you need to do is to select "Speedlock", then click on "mod1" in the lower left corner and save. The Dev mode should work now.

I hope this helps.