There are several reasons why we do not support the 'Ultima' version.
Besides not wanting to promote piracy (because we walk a thin line with what some would call reverse-engineering efforts), we have practical reasons too: the 'Ultima edition' refers to a wide range of pirated versions of the game, many of which have been modified to reduce download time, which stops certain mods working with them.
We could, of course, spend hours and hours trying to account for the hundreds of 'Ultima editions' out there and modifying our addons appropriately - all the while taking resources away from our modding projects *AND* putting our projects at risk (because our project relies on the good will of Square-Enix) *AND* making modding all the more confusing for newcomers (who will be bombarded with contrary instructions for different 'flavours' of Ultima) - but instead we have decided that this is worth neither the time nor effort.
FFVII PC may be out of print, but it is still available for purchase here and there. And there is, of course, the PSN version - don't make the mistake of assuming that the modscene covers only the PC version.
Remember that modding and reverse engineering projects do not go unnoticed. QHIMM has himself mentioned what appear to be a steady stream of visitors from Square, and I'm sure Halkun will glady relate to you his time in court, being threatened by Sony over his PSX doc. As I said, we walk a Very. Thin. F***ing. Line. - and the aggro is frankly the last thing we need.