Ok, my optimism for being able to build this has died down a bit. Made some notes about the build dependencies:

• SFML-devel: already in repo
• ftgl-devel: already in repo
• fluidsynth-devel: already in repo

• freeimage: Here is where it gets interesting. Was accepted as a dependency for T2545 in repo as R844. Last release is from 2015-03-15 and it has embedded libraries (libjpeg, libpng, libtiff, libmng and zlib) of that era. As far as I can see (admittedly not a packaging pro) debian package build has a patchset they apply to fix it up and force freeimage to use there libraries.

• wxwidgets-devel: As I noted above this needs wxwidgets compiled with --enable-webview and --enable-mediactrl which in turn adds gstreamer-1.0 and gstreamer-plugins-base-1.0 as a build dependency. wxwidgets is build with emul32 and would also need the gstreamer things in 32bit and all the way down. To avoid that ikey told me it was possible to configure the 32bit and 64bit version differently using something like this:

setup      : |
    if [[ ! -z "${EMUL32BUILD}" ]]; then
        %configure --foo
    else
        %configure --bar
    fi

But for now I get the same build error where it doesn't find the right deps. Tested without emul32 and it does build.

Will keep trying but would be grateful if someone with more experience would take a look at it and give me some hints.

@simniotiqu You need to make sure you're using the pkgconfig32 deps rather than pkgconfig