Dark, there's a camera you can use to examine the environment for platforms, it just doesn't mention it in the tutorial. If you hold down g and arrow around you'll hear a deeper solid beep for walls and platforms. And later in the game after you get the grappling hook, it makes a doo doop noise for platforms you can't hook up to. Also re your previous post, walking helps restore stamina but not health. The only way to restore health is to either make it to the end of the level or take a health potion.
Quite a bit of stuff isn't mentioned in the tutorial. Run the readme through google translate. There's a lot in there that's useful. I found I had to copy and paste it section by section into a new .txt file then translate it a bit at a time using the translate document feature. For some reason if I tried to translate the whole thing in one go, it only did the top part. Hope that helps. You're going through an identical learning curve to mine. Remember at the end of stage 1, after you unlock stage 2, you need to go back into stage 1's menu to get a new weapon from yammagin. Don't know how to spell his name. The shops always appear as the last item on the list of levels after you beat a stage, but sometimes they don't unlock straight away.
And you might find it useful to watch Liam Erven's Let's Play Bokurano 3 videos on youtube. Probably best to watch them bit by bit after you've had a good go at the stage yourself for any things you might have missed otherwise they'll act as spoilers, but there's loads of useful tips about secrets and stuff in there. And they're great if you're really stuck.

ah that one you have to cross  the room and get  the box, its hard on the first time, but try to learn the layout, and the movement of the lamp
remember, the detection menu and the camera is really helpfull

Okay I'm trying out the camera, but the way it works seems odd, for example sometimes I hit a wall and then hold g and right arrow  I hear the sound for free space, this is why I've still not  worked out where to go in 1-2, since it seems there isn't a way to get up to row 4 where the lamp is in order to kill it with my sword.

"Flacus, thanks for checking that. I think the playing of that empty space sound instead of the wall was partly why I was getting confusing at the camera, it's fixed now, I have the rope so everything is goodactually I'd missed the weapons in 1-2 and if I'd had the plate thrower I probably would've been in less distress here .

Btw, if you don't mind one more question, how do you get more amo for  plate thrower? and indeed how do you check how much amo you have for it?

Rofl, +1 from me.

What are your stats looking like? Either not enough attack or defense can really really hurt you in this game.

Dark, it sounds like you are forgetting to level up. Every now and then after you defeat an enemy you'll hear a distinct musical chime... that's your cue to hit l and level up your stats.

Thus far I've been even in stat points which is probably a good idea over all but not a good idea originally .
I suppose it's grind city for me then, though at least if I can get more amo for the plate launcher by getting it again I can grind and do something useful at the same time.

I could not get the iron balls because it seems they are on ledges that are higher than I can reach, hell I still cannot find a way out of that area if I go too far into it, it seems you get stuck down a gap that is too high for you to jump up again.

Edit: okay I did kill the bear. It actually turned out what I needed to do was use the combat log, since unfortunately it seems there is no other way of knowing when weapons do zero  to an enemy, eg, the rope can kill insects but can't do green slimes. It seems you can only damage the bear with the pipe or the plate thrower, and I didn't realize you had to go back and get the plate thrower again to get more ammo.

Still no luck getting those iron balls, indeed I have had to exit again from that area since it seems there is no way out without either the ability to jump higher or climb ledges. I suspect I am missing something in the jump controls (really after translating the entire game it seems odd the readme isn't translated too since I would've thought that would be relative easy and unfortunately the tutorial does not seem to go into enough detail on a lot of commands).

I am however now on stage two and tangling with the desks. Annoyingly it now seems I can't! get more plate thrower ammo from the first stage. Still I am soldiering on.

Dark, for that area, you need to make use of the camera with the g key to map out where you are. for 1.1, go to coordinates 36-0 where, in that area you get stuck. Jump up to the left onto a ledge, and from there you should be able to jump repeatedly to your right to find the higher ledges and the iron balls. Also remember that you don't have to always rely on your plate launcher. Look at the weapon stats... many of them will do more damage as you increase your attack stat. Remember also to get your long sword from the stage 1 shop.

Hi Assault freak, thanks for that, I got the balls, that is cool, though it is a little irritating my plate thrower is out of plates and I can't get anymore.
what I meant in terms of weapons was that the bear only seems to be affected by the plate thrower and the bat, the rest of the weapons do zero damage (or at least the shortsword, longsword and masamata do) and the bat does four hp a hit, which, given the bear has I believe something around 1200 hp is not going to be exactly too effective .

With other weapons I'm alternating the long sword and rope, the rope for lamps, the long sword for most other things, since it seems the damage on the massamata isn't good enough and my attack stat means the bat is now less damaging than either sword even though it has a higher over all damage.
That being said, I will confess the grinding is getting a little  tedious, given I'm level 12 currently, and yet am still! having to hit those desks waaaay too many times to kill them as compared to the damage they do and the number of them there are, indeed I have lots of coins and nothing to spend them on so far .

Hi.
I'm stuck in 5.4, the boss level.
At first, I kill few of those small creatures on the ground, using red pachinko balls.
Then, I climb to the tree to kill the bigger one. I could kill him, but those small creatures climb after me and kill me.
What can I do, how can I kill the boss without being killed?

@dark
I recommend you leaving the plates for 2.3.