Hey WildEep, got something for you.
http://2style.jp/bowline/ds/tool/random/walker.html
This is a tool created for Pokewalker abuse.
Input the seed the way you're used to.
X受取 is the number of the pokemon you transfer.
1 will give you the used 192 for example.
Press the button unter the number and a list with the Pokewalker corresponding Nature on that particular Seed is given out -1.
Japanese calc different so 192 is actually 193.
A bit easier than modulo 24 and calcing back and fore and stuff.
I just tested this, it works.xD
If you want any translation of that don't hesitate to ask.