Are you in "underground" mode?
Nope, I know about underground mode and it def wasn't that. For some reason all my previous exploration was gone. I've had this sort of problem with mapwriter before, altho it usually works perfectly. It's def my favorite of all the mapping mods altho other mapping mods have better waypointing. Can't have it all in one package, I guess.
Anyway, I already deleted that world and started another one, and the same thing happened. All the exploring I did yesterday is gone, all I can see on the map is the circle around where I am presently. I've been using my boat to map out large portions of my world and I think perhaps that might be the issue here. Boats really suck in Minecraft with the desync/lag issues or whatever Mojang did (they really f'ed boats up bad)... but it certainly isn't a problem with InfiTech modpack, it occurs with all modpacks. But if Mapwriter isn't going to work properly with this pack, I don't think I'm gonna be able to play it for very long. Mapping & waypointing is essential to playing the game IMO.
Speaking of boats, it's sad they don't work well because they're awesome for early game:
(a) you can map and explore much quicker than on foot
(b) you don't lose hunger while spending time in the boat
(c) you can safely spend the night in a boat without fear of mobs
Since I can't find any coal in the first few days of exploring, and since we can't make charcoal, I never have any light sources during the first night or two, so a boat is my best strategy. Too bad I go thru a boat every 2 minutes... I'll be 20 blocks from shore and the next thing I know is my boat is broken and gone... and there are the sticks and wood next to the shore. I was 20 blocks from it, but the game thinks I was over there and hit the sand? Give me a break... If I have one hope for the evil big corporate Microsoft (who thinks they are a "gaming" company but excuse me while I laugh out loud at that idea), I hope they fix the way boats work. Darn it!