LyX - Error when including a file with a listing

Question

I'm new to LyX/Latex and this is my first project in which I'm using it, so I don't know if I was specific enough in the title.

To write this project, I was given a template made of multiple files:

• outline.lyx;
• solution.lyx;
• simulation.lyx.

All these files are included (with input) in a main file, let's call it main.lyx.

In solution.lyx I used the ERT:

\lstinputlisting[caption={Component}]{design/component.blif}

to make a listing that "includes" directly the source of my code, instead of having to copy it manually. The directory "design" (in which there is component.blif) is in the same directory of solution.lyx.

Now comes the problem. If I put main.lyx in the same directory of solution.lyx and generate the PDF with pdflatex, everything seems to work fine. If I put main.lyx one step "higher" in the path (so that includes, for istance, "ex01/solution.lyx"), LyX gives me the following error:

Package Listings Error: File `design/component(.blif)' not found. *** (cannot \read from terminal in nonstop modes)

Does anybody know how to fix this problem? I would really like to put the main file one step higher, so that I can include multiple files from different sub-directories.