Updating to the new 1.10 drivers fixed FFXI itself, more or less. I should have done this earlier, but I've been working on this for a long time and no previous versions had worked so I didn't think it would matter.
Unfortunately, high-level FFXI is nearly unplayable without Windower and related plugins and when running Windower, even in true-fulscreen mode, the application simply will not acknowledge the existence of iz3d. The overlay is not shown and keys don't work.
This issue has become a lot less important, obviously, but if someone at iz3d could maybe shed some light on why that would make a difference it'd be great because vanilla FFXI is extremely unimpressive.
The "meat" of Windower is the attached "Hook.dll" which is available, along with the launcher for it, at www.windower.net
. I understand this is low priority to a team with hundreds of issues, but it would be excellent if it was something easy to fix.