Rudi Gaelzer <rgaelzer <at> gmail.com> writes: > Is it possible that the texlive 2010 version in F15 is lacking the > needed packages? I > have the F14 version of texlive 2010 installed in another workstation > and that works all right.
I don't think so; the only packages "by type" uses are amsmath.sty and amsthm.sty, and without those all the AMS theorem modules should be borked. I just tried on my laptop (Linux Mint, TeXLive 2010) and got the same error you did. Then I looked in ~/.lyx/layouts and saw that I had old versions of some of the .inc files used by the theorem modules. I deleted those, reconfigured LyX and the module is now working. So you might check there. Paul
