Quick update!
I now have the following sections identified and extracted:
0x1400c-0x1b8cd - INCOMPLETE - Main game story dialogue.json
0x1b8d6-0x1bfdf - COMPLETE - Intro_scrolling.json
0x1c040-0x1c90d - INCOMPLETE - Game menus and save screens.json
0x1c952-0x1ca2b - COMPLETE - Further game menus.json
0x1cbad-0x1ccac - INCOMPLETE - NPC_names.json
0x1d59f-0x1dc7a - INCOMPLETE - Weapon names.json
0x1dc87-0x1dee3 - INCOMPLETE - Shipboard_menus_1.json
0x1e71c-0x1ea86 - INCOMPLETE - Professor lab screen.json
0x1ea88-0x1ec00 - INCOMPLETE - Mecha overview screen.json
0x1ec08-0x1edfa - INCOMPLETE - Possibly Closing Credits?.json
0x1ee0f-0x1f0df - INCOMPLETE - Game Credits.json
0x1f0f4-0x1fb3f - INCOMPLETE - unknown.json
0x28086-0x29efe - INCOMPLETE - MICA and player dialogue.json
0x29efe-0x2a1af - COMPLETE - Intro_cinema.json
0x2a74c-0x2a930 - COMPLETE - Lights_out_after_intro.json
Virtually all of the game menus are now in english, with just a few (one or two in the hangar/mecha screen and the two 'save game', 'save password' in the med bay screen) left to find.
A good chunk of the weapons/items that are available from the start of the game have had both their name and description translated into english (see images below), but I've yet to find the location of their stats (weapon strength, size, 1/2handed etc).
Translated and retitled most of the main 'display mecha stats' screen.
Translated all of the 'equip your mecha' screen.
Mecha names need translating.
Some NPC names need translating.
Found the main game dialogue and extracted it.
Found the dialogue that is shown when scanning a planet - it's also extracted.
Translated all of the pause-game menu options (heal/repair/show item screen etc), as well as the actions you can perform from there; choose a medic and heal one of your party, choose a tech/engineer and fix one of you party's mecha. etc.
Here's some the images of the new progress: