Hi Daniel,
the way you describe your products as “Windows XP based devices” gives me the impression that the (low-level) Gaze SDK would be a better match for your needs than the EyeX SDK. And the Gaze SDK does work on Windows XP. Showcase doesn’t, but maybe your company policy allows setting up a more recent Windows version on a developer machine for experimental work?
We made some major changes to the Gaze SDK last week to make it better aligned with the EyeX SDK. It’s so new that we haven’t even had the time to announce it properly yet, but it’s all available on the REX setup page. Essentially, what we did was to remove all the configuration software, so that developers who use the Gaze SDK get the full responsibility for configuration. It makes more sense to do it that way, when the intended use is for embedded/single-application environments. As a side effect there is no need to install the .NET framework anymore, only the VC++ 2012 runtimes — and those are available for XP.
Finally a word on why we decided not to support Windows XP for the EyeX Engine: A lot of things changed in the Windows API related to display handling between XP and Vista that would have forced us to write (and support!) special code for Windows XP in the EyeX Engine. The cost-to-benefit ratio was too large. And apart from that, Microsoft has communicated an end-of-life date again and I expect that this time they mean it.