Since the instructions for compiling WindowMaker (0.92.0) with drag and drop support seem to be scattered across the whole 'net, I'll report how I did it.
- Download WindowMaker and untar the downloaded archive
- cd ~/Downloads/WindowMaker-0.92.0 or wherever it is
- Download this patch to get WindowMaker to compile with gcc4
- patch -p1 < ~/Downloads/windowmaker-gcc4.patch
- open src/misc.c at line 842 in your usual editor (e.g.: vi +842 src/misc.c)
- comment out lines 842, 843, 844
- save, quit editor
- ./configure --disable-locale --sysconfdir=/etc --localstatedir=/var --enable-usermenu --with-appspath=/usr/local/GNUstep/Applications --with-gnustepdir=/usr/local/GNUstep
- in file src/wconfig.h, uncomment line 71 that says /*#define XDND*/
- make
Become root (login as such or su)
- make install-strip (strips the debugging symbols away, installs leaner binary)
- ldconfig