I'm not too familiar with Firewire, so this may be of no help, but I'll offer this on problem #1:
I've found that quite often when a flash memory device is connected to XP, the OS will assign it a drive letter that is already in use. When it does that, it will seem as though the newly attached flash memory isn't there at all. It won't even give the pop-up dialog asking if you want to open or view the files on the card.
To check for this, with the flash media conncected look at
Disk Management located in
Administrative Tools. You should see the flash card listed along with your hard drive, CD/DVD drives, or any other storage media. Compare the drive letter of the flash card with the other devices. If it's using the same letter as another device, right click on the listing for the flash card and select the "Change Drive Letter and Paths" option, then just pick an unused letter of the alphabet.
Like I said, don't know if this is an issue with Firewire, but maybe it'll help.