Never had a problem with this using TC.
a) booted an official WINDOWS CD inside QEMU hosted on a Tiny Core PC
b) booted Tiny Core inside a Windows Hosted QEMU that was running inside WINE running on a Tiny Core PC.
c) booted TC using QEMU on various flavors of Windows (what many Windows users probably want to do)
d) created and booted ISO's inside QEMU that had TC on them
e) While in QEMU had access to FOLDERS that appeared to be DRIVES to the QEMU environment.
f) Had access to two way TCP/IP network (internet) traffic, browsers, ftp etc.
g) Had access to scuzzy pipelines, though these don't always behave.
The only real issue that I haven't really fixed is the inability of QEMU to access a live USB drive as a drive I can read/write to; I always seem to have to stuff data in a folder and make that a drive. And WINE absolutely doesn't seem to like real drives; always going to a folder that appears as a drive to the WINE environment, though somehow (not quite sure) I got a CD ROM to mount and was able to write to it; though not sure if I could repeat that. I was kind of fearful WINE would zap the wrong scuzzy channel and take out a USB drive.
Beyond that, Windows desktops inside QEMU or WINE running in a TC environment, or TC inside QEMU on real or emulated Windows PCs are a piece of cake and work easier than I ever thought they would.
If you get stuck, let me know.