Do the makers of your Siig card make their own drivers? You might want to see if there is some update there... On the other hand, you might want to check in your Hardware Manager to see what the actual driver is in your 1394 Host Adapter - that might need an upgrade to handle FW800. Also, do a search on this forum for references to SidSpeed - some Windows XP installations cause the default Firewire connection speed to revert to its slowest setting. Adjusting this will restore full functionality to your Firewire connections.
If you're going to chain your devices off of one Firewire port, the hard drive should be between the computer and the Fireface - just about all DAWs like to work this way, and in fact, Digidesign stipulates that this is how to run Pro Tools with one of their Firewire interfaces (whether or not you're using Pro Tools, this is one instance of a DAW and hardware manufacturer stipulating how to set up a Firewire chain).
I, too, have a Glyph drive - one of the older 062 RAID drives. While the drive is solid enough, the Glyph Manager 4 software I'm using is a little flaky with my XP SP3 installation, and I've found it's best to set its options so that it doesn't launch at boot up, or lurk in the Tool bar after closing the window - it really quits. I don't know whether the use of this program is needed with one of their non-RAID drives, but I thought I'd mention it, in case it's installed on your system.
I've run some preliminary tests on my system to check for track counts and sample rate, and have found I can run 16 channel 48 kHz. sessions all day long with no problem - and this was with my Fireface connected to my computer's FW800 port and the Glyph drive connected to the FW400 port. Recently, I've been investigating using higher sample rates, and have not run into problems running 16 channels at 96 kHz. More channels than that exceeds my I/O capability, but I have set up sessions for playback - mixing down to two channel output - of more than 56 channels @ 48 kHz. Everything appears to be well within spec, and all runs smoothly. My DAW is Pyramix.
Fireface 800, Firmware 2.77
Drivers: Win10, 3.125; Mac, 3.36