CORE Guide?

For industry you have to wait for the right tech. I'm afraid I can't answer the other questions off the top of my head! Well, I intuitively know the difference between the different types of engineer, but I can't remember the figures.

In general, just asking in the forums is the best way to get answers though. People are always happy to help, and I'm pretty sure there's no up to date documentation. With a labour-of-love project such as this, manuals are always last on the list

apart from the increase of some values, which you can see in the build screen, combat engineers increase the dug-in cap to +40 (from +20) for the division it serves in. constr. engineers increase speed and other values
you can build them maually, check for the brigade build menu right below the land divison build menu
for some countries IC construction is disabled at the start. they get unlocked by researching into the appropriate (heavy)industry techs (you can read it in the tech description)

Have you scrolled down the brigade list? (Sorry for asking the obvious)

Combat enginers are not always named in as english but in the countrys language. Their designation is "eng" while the contruction enginers are "ce". Btw what country are you using?

If you dont see the contruction enginers, towed arty you propbably need to unlock more infantry motorisation tech's. They atlest unlock them but meny contry's have them already unlocked. Also a good way to make sure the info you are given is accurate is to post your checksum for base game and the mod you are using. AoD = SUBR, and CORE = ZJDB. To find the checksum look at the top right corner of the games main menu(ingame), not lauchers.

Also did you get the latest CORE version instread of the one you asked help for earlyer(0.61)? While it is under "open beta" its nearly fully bug free and close to final version of the 0.62.X chain.

And sorry if there are more typos than normal just got up.

If you can't build Industry that's to simulate the effects of the recession. First closed factories will open their doors again, before new ones will be built... They unlock with the later recovery techs (1938 recovery tech IIRC). For the rest you basically need to research first. Within CORE the tech tree is interwoven, i.e. require research from the other tech trees as well to unlock, and sometimes are only activated by event. A good example is the Post Treaty Warship Development Doctrine on the naval doctrines tab, which is mandatory for the larger ship classes to unlock on the naval tab, and is activated by the Partial Mobilization Event. Also a good example is either the 1935 Light Tank Brigade Organization or 1935 Tank Brigade Organization on the land doctrines tab. They are mandatory for building tank units, and will determine whether you can build 6-Battalion or 9-Battalion divisions.
I know the manual isn't too recent, and helps only somewhat in understanding the basics of CORE. Usually a playthrough or two will get you learn the ropes, and the tech files in the mod-CORE2\db\tech directory list the requirements and activations for each tech, should you wonder why you can't research it at a given time. And the forums are always a good place for questions. And it might be a good idea to mention which country you are playing as well.

As to the 0.62.7 Open Beta version, well that one would have been the final release for 0.62, if I had not started on an image spree... I really recommend using that version, especially as it has over 200 new, unique event images compared to the previous 0.62.6.

Hmm you had the game in another language? Ithink it is atlest missing some translations so you might get alot of UNKOWN_STRING's. Just tested the game in german language version and yes still missing too much stuff to play. Also if possible make sure the checksum's are correct at evry install step.

CORE is to be played with english language.