I'm getting the hang of Quest!
But why is that I can't change the Basefont to FIXEDSYS or some other mono-space fonts?

I wanted to have a font similar to this, but apparently the Base Font can only be picked from the list. I tried typing Fixedsys and 'Fixedsys' and any other font really and it just sets to default Times New Roman
(Not using Web Fonts because I want the same font to appear in local offline as well)

Am I doing something wrong?

http://i.imgur.com/imeBrPE.png

Sounds like you know where to change it, just not to what...
Have you tried Courier New??? It is a fixed spaced font.
Actually, 'Lucida Console', Monaco, monospace looks a little better...

I think it's that they want to make FIXEDSYS a base font rather than rely on a Web Font, but the base fonts are more limited. I'd say is there a better question like can extra fonts be added into the game as a base font, through a library or plugin, so they can be local offline too?

Personally, my own game uses webfonts due to the unlikely chances of someone managing to both download it but then also not have a net connection to play it. But, if you're using a very limited few fonts, a way to have them packaged with the file would be good so they're always there.

This MAY help:

You can convert a font to Base64 (using the BASH! shell), then embed whatever font you'd like into a game.

See this post:
http://textadventures.co.uk/forum/samples/topic/-sem6m7qe02a6jr9spodig/add-css-and-javascript-to-your-game#de3f7b33-2496-4cf9-ba84-d86d0c943935

That method uses SetWebFontNameto load the font initially, then you can switch in-game by using SetFontName in your scripts.

Here's an excerpt from The Pixie's wiki:

You also have access to web fonts. These are provided on-line by Google, and by default you can access just one in your game. To use any more, you need to call the SetWebFontName to pull the font off the internet, and then SetFontName as normal to actually use it.

  // Pull the fonts off the internet
  SetWebFontName("Wallpoet")
  SetWebFontName("Admina")

  // Now we can swap between them as much as we like
  SetFontName("Wallpoet")
  msg("This is in Wallpoet")
  SetFontName("Admina")
  msg("This is in Admina")
  SetFontName("Wallpoet")
  msg("This is in Wallpoet")

From: https://github.com/ThePix/quest/wiki/UI-Part-03:-Fonts

Here's a link to my game, which has an embedded customized font. (The > is a revolver in my version.)

This is incomplete, by the way. ( I'm currently porting it to Quest.)
http://textadventures.co.uk/games/view/rr9vezzxkeaovamsaqgxcw/they-call-ya-mister-quest-prototype-in-progress

If you enjoy it at all, the complete GLULX version is here (currently unlisted, pending testing):
http://textadventures.co.uk/games/view/ogj8kixyx0emjknru3nckg/they-call-ya-mister