posted a few Q&As on the front page (reproduced them here as well). please don't hesitate to ask me any questions (in this forum or on sitemail is fine).
In the one-round supplemental draft, which franchises can be selected from?
Only the 6 franchises that debuted after 1969 are eligible. Those are TOR, SEA, COL, FLA, TB, and ARI.
Do the Nationals count as part of the Expos franchise?
Yes, and this applies to all franchise continuations, whether through relocation, name change, or whatever.
Do players taken during the "main" player draft also eliminate them as choices during the supplemental draft?
Yes, players are exclusive across the entire league. If somebody drafts Curt Schilling during the main draft, he cannot be drafted during the supplemental draft.