Ok, looks like I have a lot to update the OP with, so good work guys so far.
I'll update on where I am :/
Last night I got my IVs->SEED application working and from there started working on taking that seed and some information about when you reset and allowing a hunt for the initial seed.
It's not going to hot. At this point I've either messed something up or misunderstood the forumla (which seems strange as I can use the formula and get the same sample results as the initial japanese page) OR the seeding formula has changed for the english version (unlikely, but I will test it).
Here is how I am going about trying to find the initial seed right now:
Given Nature/IV's find a list of valid pids for a monster (usually one. sometimes more) and create a list of these "monster seeds". The user then enters the following information about when they reset: Year, Month, Day, Hours, Minutes. (missing are: seconds and delay on continue screen).
Then I do this for each one of the "monster seeds":
I use this seed to go backwards through the previous seeds (a maximum of 10000 times, which is way too much, but I wanted a high number for testing) and then for each one of those seeds I do the following:
I use the formula on page one and calculate every combination with the values the user entered for Year, Month, Date, Hours, Minutes and cycle through seconds 0-59 and delays of 0-36000 looking for a match.
I keep a list of all matches along with how far they were from the "monster seed" and what the seconds and delay were that needed to be substituted. I generally get a few possible hits, but the problem is they'll have HIGH delay numbers or be offset -1000 back from the initial seed when they really should be withing a couple. I'm very frustrated at this point, but will keep messing with it.
Jonny -- If you see ANYthing about the initial seeding in the pages you are translating please let me know. As much different information to verify my method would be good.