Before I found out there were tools that people like Battlebelk and Phobos and others had made, I did a lot of Hex Editing on the .lvl files.  Time consuming until I found what I was looking for.
As far as I know (and what has been stated earlier), you cannot replace a shorter one with a longer one (there are a few exceptions that I have found, but the mission.lvl won't let you get a longer one).
To change the units, first you must call up the all_inf_basic(*null*,desert,jungle,urban,snow) that you want.  Don't type in *null* LoL.  For example:
Search tat2.lvl and go up a little to see the units.  Stop at SIDE\all.lvl
Change all_inf_basicdesert to all_inf_basicjungle. Then go down and change all_inf_soldierdesert to all_inf_soldierjungle.  Note that you cannot change the rest because only soldier has "desert".
Save and go ingame.  Only the Soldier (jungle), pilot, and wookiee will show up because I think that the .req for "jungle,urban,etc." doesn't recognize the vanguard and marksman unless they are jungle too.  (But jungle looks the same as if you had just all_inf_basic so someone got lazy somewhere or I'm missing something... So i would just use all_inf_basic until someone finds any difference...) 
I have not found how to Hex Edit reinforcement counts. And those objectives are set in the core.lvl I think.

Edit: Soldier is only class with urban extension that i see...

I'm such an idiot! LoL. When i thought of radius, i thought of primary weapons, and forgot about the thermal detonator!

I was looking for a weapon with an effect radius, but the fusion cutter is nice to know too. Thanks Unit 33 and Sereja
Bamdur's post is more along the lines of what I wanted. Would I just input AddHealth = "5" or something like that and then add Radius into the weapon odf, or do i need to edit an _ord file to achieve this?

Edit: Also, what weapon on BF1 has a Radius command?

Now I know that it CAN work, I just am not sure quite how to create this.  I downloaded SWBF2 Mod Tools, tried crossing them over (knowing full well that it probably would crash), and it crashed.  I don't have the source of the level so all I know is that it works just like BF2.

Endor.  Fun to take out the Ewoks, but also a fun sniping map.  Also speeders make this a challenge if you take a route through the trees.  Downside is that if you get an ATST and a couple pilots and know exactly where the Ewok traps are, the level can get kind of lopsided fast.

Personally mine is the side.lvl and mission.lvl.  They are the main ones that I mod at the moment and seem to have the most impact on the game unless you are really experienced with modding the core and common (which take a little more effort and time but show a lot of promise).  All of them are fun to mess around with though 

I was interested to see if anyone knew how to make a health recharge (like on BF2 with the Bothan Spy giving health) on BF1.  I've messed around with the "powerup" weapon held by pilots, but no luck.  Maybe combining the health droid with it? I'm not quite sure.  I would look at the BF2 Tools but seeing I can't get them right now I'll have to ask here
Thanks!

The great state of Pennsylvania. Although my dialup would make you think I was on Mars because of how slow it is.

I know that this topic was pretty much dead, but I found an old link in my archives that may be of use to those who want to play 1.0, if only to make fun of us.
http://boygamer9.webs.com/swbfversionswaps.htm
I don't know all the details, I just got it to work. I always did the "Copy your 1.0 folder and then get 1.2" but found this when I was looking for something completely different.
1st is to go to 1.0, 2nd to 1.2.

Edit: might help if you go for the 1.0 no-cd just in case. Might disagree with the 1.2 dvd... i don't know...

Yes, the other 4 can be primary, I've been testing them. It's just that great 5th weapon can't have geometry (as already stated).
Why WEAPONSECTION though, I'm wondering?  I've tried using the WeaponName5 (etc) and it didn't do it.  Any explanation for it?
Is a 6th weapon like overload or something?  I tried with the same (imperial mines) as my 5th weapon, and crashed still.

  Stupid Vista.
It was the virtual store thing. The reason that it didn't show up on 1.2 was because in order for my ZeroEditor to work, I had made a modded BF 1.2 folder not in Program Files (x86) and used that.  My backup 1.0 folder was in Program Files so it kept the original. Sneaky, and probably smart for someone who has no clue what they are doing.
I've made about 5 backups to my folders just in case something happened a while back, I have a big enough hard drive anyway.
Anyway, it works now, so thanks.

Basically my 1.0 files won't just be nice like the 1.2 .lvl files will. Maybe it's just stupid Vista.
Example: I made a mission.lvl file using the builder, and made Cloud City 150 Rebels with all classes and 350 Empire with Scout and Dark Troopers.  When I copy this to 1.2, it works great, no hitches at all.  When I copy it to 1.0, there is no change, somehow it sticks with my original mission.lvl, no matter how many different ways I copy my .lvl over.
I tried to make it as simple as I can, but I'm not sure that my problem is understood. Maybe its just my comp hating me.
Thanks for helping.

But what is puzzling me is that I used them, and they work great on 1.2, so I wanted to see if they would on 1.0.  But they don't for me.  I put my new mission file in there and... I'm stuck with my same old mission file (which I Hex Edited already but I tried the other builders on ones that I didn't Hex edit so I know that's not the reason).
I know how to do the Tusken Raider thing through Hex, one of my favourite snapshots I ever got was on Cloud City with Ewoks with Blaster Rifles. So I can do something, just wish it was easier.
By the way, if I ever (not really with dialup...) hosted a server, I know the clients joining the server would read my mission and bes2 files, but would it respond to something like a Ewok-Empire server?
I'll check for answer in morning.
Thanks!

Hello all.
I think this is where I'm supposed to put this...
I'm an average (at best) modder. I learned how to do some basic Hex Editing and that's pretty much the extent of any useful modding if I could ever host a server on dialup, but I do it for fun for myself though. I've never really worked with the 1.2 Mod Tools that much until recently. I decided to try using them.  I used them on 1.2, they work obviously.  But on 1.0 it is very... curious.  I used the Common.lvl builder, noting that because of the differences it probably would not work.  Start the game... nothing happens out of the ordinary. 
I tried the Mission.lvl builder, thinking that it may work because they are almost (if not exactly) the same. Knowing that the mission.lvl did work in 1.2, I wanted to try in 1.0. When I place my munged mission.lvl in my folder and just replace it, it's exactly the same as before I used the builder.  So I copied both files back in, checked my custom one (named mission(2)), and then deleted my original.  I closed and reopened my mission file and it was good.  I go ingame... same as before.  I then renamed my custom and checked it... and it went back to the original.  I have also done this with the Side builder.
In the past I've tried to copy my Hex Edited bes2.lvl to my laptop because it was a pain to get it how I liked it, and it reverted to original ingame also.
I know how to Hex Edit to do some of the stuff these builders can do with it, and it will stay intact when I do that on 1.0, but I'm trying to help some of my (few) fellow modders on 1.0, and this would make it much easier if this could be figured out.  So "Just use 1.2" is not an option.
Thanks!

I agree with previous posts on the fact that 1.0 is more social than 1.2.  I like 1.2 because it decreased lag (although I still have dialup... :/ ) and there are many, many more players to test yourself against and gain in skill.  Mods are also nice too.  I guess I'm still attached to 1.0 because of the bond most of us have built.  Before we had the chance to get 1.2, we had our 1.0 clans and we knew everyone in them.  Wars (actual enemies) are very uncommon now.  The last clan to really have problems with 1.0 wars was {snp} (read their history for more details).  Fun wars are not likely to happen either unless you pick a perfect time.
What I've noticed over the years is that those who play 1.0 transition well into 1.2 if they find servers that are more geared to 1.0 (Sniper Tournament, etc.) AND practice 1.2.  And that skill translates back into 1.0 if they wish to play both versions, making them very formidable in both versions.
There is pros and cons to both versions... so I play both