FF VIII plays perfectly fine. Believe me... that's the first thing I tried heh. However, there are a few things you fail to include in your post:
- What version of WiiSX are you using?
- What version of HBC are you launching WiiSX from?
- What device holds WiiSX and your ISOs?
It is worth to note that WiiSX on HBC 1.0.7+ is kinda buggy (speaking from personal experience), and may range from simply not finding your files to not running anything at all.
Also, did you rip your own ISO or downloaded it somewhere off the net? If you ripped it, make sure your disc is clean and as scratch free as possible and try to rip it again. If you downloaded it from the net, it might've been corrupted while downloading, or was simply a bad rip. Try finding a different ISO and try that one.
Good luck.