2006/8/3, Marc Vinyals <[EMAIL PROTECTED]>:
Some notes: first, and also from The Comprehensive LaTeX Symbol List, you need to \usepackage{eurosym} to get these macros defined.
I've added \usepackage{eurosym} to document preamble and pasted some euro symbols (appears «?» on LyX) and the ps/pdf output also shows «?» instead of euro. Same as without eurosym.
It's strange, though, that LyX doesn't handle direct \euro keystrokes while it has no problem with German ss or Latin ae. It might be a key-mapping problem, since AltGr+E == Ctrl+Alt+E could be bound to a menu item or whatever. This problem exists with lyx-1.4.2-gtk too, but may be specific to the ES keyboard layout.
I think there are two problems here: what you describe (key-mapping problem) and make lyx euro-aware.