> I do not think that even a InsetGraphics object has to be a valid > file. If I have Logo_INRIA.pdf in my TeX path at work, I want to be > able to use it. Currently, LyX does not find graphics through > kpsewhich, but there has been a request for that (and I think we > should do it). Therefore we should be wary of adding new obstacles in > this direction.
When I re-think this problem, the current approach should work just fine. It is true that these files might be anywhere, but EmbeddedFile will *not* embed them if it can not find it. As long as the latex output is corrected written through the use of a combination of path and meta information (see my new patch), I do not see any problem here. Bo