First of all, I'm playing this game for the first time ever. Very glad I did. I don't think I've played such a thought provoking game before. Anyways, I just made it to the Lower Ward and I noticed that I can now use the map to travel which is great. The problem is that now it takes 4 hours just to go from one zone to the next. It takes 24 hours just to walk around the hive and go back to the Lower Ward. Seems a bit excessive to me. Any way to change this or no?

It is possible to extract and edit the WORLDMAP.WMP file to reduce travel time. However, a copy of the file is stored locally for each saved game, so doing this halfway through probably isn't going to have any effect. You'd have to start over.

EDIT: The All-Inclusive Pack from SKARDAVNELNATE had an edited WORLDMAP.WMP as an extra, I think, so you can try to find it. It's still very unlikely to work on a game that's halfway completed.

SPOILER ADVICE: As an alternative, get the "metallic cube figurine" from Vrischika's exotic item selection, in the Clerk's Ward (costs 1500 coppers), then figure out how to unlock it (ask around, there are characters in the same ward who might know what it is). If you get control of what's in the cube, you can go inside at any time and ask to be teleported around Sigil. It's tedious, but IMO is better than having Dak'kon and Annah constantly tired.

Thank you for your answer. How would I go about extracting and editing the WORLDMAP.WMP? I haven't been able to find it in my Planscape folder.

Right, it's packed inside the datafiles, so you'll need a program that can parse Infinity Engine game data (see below). If you choose to edit it, make a backup of the Save folder before starting, just in case

Here's SKARDAVNELNATE's pack. The edited main WORLDMAP.WMP is in the "Extra\Worldmap" folder. It goes into the "Override" folder of your game installation, but it won't affect the saves.
http://www.mediafire.com/download/1dnoytx2m09/Torment20080606.zip

Manual editing goes something like this:

1. Get yourself a copy of NearInfinity (http://sourceforge.net/projects/nearinfinity/, runs on Java), launch it and point it to your PS:T folder (Game -> Open Game). The left panel is the game data browser, so you can access the packed files from there.

2. The main file will be inside the WMP folder. Select the file and go to the Edit tab. If you used the edited one already, read through the instructions and start at point 7.

3. On the Edit tab, double-click the line "Map 0", or select it and click "View/Edit".

4. You should see a list of available areas numbered 0 to 19. Double-click the "Area 0" line, or select it and click "View/Edit".

5. At the bottom of the table you'll see the list of exits from that area. That's the source of your problem. That "Distance scale: 1" setting, specifically. Select the first exit/link, click "View/Edit" (or just double-click it).

6. The "Distance scale" field is set to "1". Double-click that "1" and edit it to "0". Close that last window and do the same with all other links and areas until all of them are set to "Distance scale: 0". (Not all areas have links, just the first 10 or so; those are the ones shown on the map.)

7. Look at the "Save" folder (in NearInfinity). Each subfolder represents one of your saves, and each contains a copy of WORLDMAP.WMP. You want to edit those, too, or at least the one in your latest save.

8. When prompted (usually on attempt to close NI), click "Save changes".

That should do it, I think. If that doesn't work or if the edit process seems too much of a hassle, you can still go for the cube workaround, it pretty much exists because of the travel time issue.

OK, I edited my saves successfully, but when I try to save the main WMP file I get "Error while saving WORLDMAP.WMP"

Nevermind, my Planescape folder was read-only, that's why I couldn't overwrite the edited WORLDMAP.WMP. Near Infinity worked like a charm. Thanks a lot for your help.