Node-Building Problems? Or something else?

[Pyro the Magma Fox]

I am trying to make a level which should be in an OLDC, no matter when it is, but when I load a level into 3D mode, I get just a black screen and when I test the level, I can walk in air and see all the control sectors...! What is going on?

EDIT: If you have a problem like this, SHRINK THE LEVEL!

 

[Internet Explorer]

...all the control sectors

So I'm guessing this happened in the middle of your level building, right ? The last solution is to open a backup of your level (which is automatically created and updated when you save with SRB2 DB. It is created in the same folder as your wad, with the name "nameofyourwad.backup1, 2, 3 or 4.) If you're working on your level since a while, the last backup should be nameofyourlevel.backup3.
If this backup has the same black screen problems, open another wad that someone else made, and tell me if this one works. If it doesn't, then that means your DB should have a problem somewhere... so I suggest to reinstall it, I usually do that when I get problems in every maps I load.
But, only reinstall it if all the maps you load don't work ~

If the other maps work, please tell me, this means you made a bad manipulation somewhere in your map, so I'll try to find what is it.

 

[Pyro the Magma Fox]

It's okay, I found my level was too large. lol

 

[Internet Explorer]

Heh, okey. A level can get problems with its size when some sectors go over the red square, used to a limit.

EDIT : Okey.

 

[Pyro the Magma Fox]

It was inside the red square lol