eeee...I've had problems trying to get kqemu into it
kvm seems to work, and I can get portable-kqemu.exe for you...
Being that I'm not a coder of any sort, my ignorance of such things is high.
I can barely do "Hello World" in cursive, much less any kind of programming lang.
I originally got the qemu from billix-0.18, then found the qemu in tinycore-2.0
and stole it, which is probably what you have, maybe 9+ or 10?
I read somewhere that kqemu works best with qemu-8+, but not sure...
Also, there seems to be something in slackware that really slows it down?
even running fluxbox was about the same speed as kde, which means there's something in the background straining qemu.
for reference, a full hd install of dsl-4.4.10 boots in an amazing 35 sec
on portable-qemu! that's from boot to desktop.
it is the fastest, with dsl frugal 2nd at about 55sec.
tinycore and puppy each about 1min 10-20sec.
How long does your portable-slack take?
I think you should try to build slack specifically for emulation
remove any unnecessary items/apps and turn off most services too.