Multiple Questions

[Bullet-time]

Hi guys,
I´m still working on my first .wad, and while learning, many questions crossed my path.
Hopfully you can help me with some of these:

1.) How can I use high-resolution textures?
2.) Why can´t I draw shorter linedefs than 2?
3.) Is it possible to make floors? First floor, second floor...
4.) I can´t use my own sprites. DB shows them correctly in 3D and 2D mode, but when I test the map, DB just uses the (replaced) sprite.
5.) Why are these Textures hanging from the ceiling?
http://img119.imageshack.us/my.php?image=aawx8.jpg
6.) How can I close unclosed sectors (without completly redraw them)?

Jeez, these are some questions :)
I hope you can answer some of these.
Thanks
Bullet-time

[Illdo]

1.) How can I use high-resolution textures? Use a port that allows them.
2.) Why can´t I draw shorter linedefs than 2? Maybe your WAD editor is set so that you can't do so.
3.) Is it possible to make floors? First floor, second floor... Not actually. But you can try and use teleports to simulate it.

5.) Why are these Textures hanging from the ceiling?
http://img119.imageshack.us/my.php?image=aawx8.jpg
Try fiddling with their "lower/upper unpegged" bits.

[Aliotroph?]

3.) Is it possible to make floors? First floor, second floor...

Yes, if you're using Legacy, GZDoom or Vavoom. I think you can in Edge too, but I might be smoking something.

6.) How can I close unclosed sectors (without completly redraw them)?

Sure. You can edit the properties of any sidedef and change which sector it's assigned to. Then you can close sectors, make them into different ones, or even do weird, potentially game-breaking things.

[hawkwind2]

3.) Is it possible to make floors? First floor, second floor...

Risen3D also supports this feature.

[Bullet-time]

Thanks for the answers.
But how can I do these things with DoomBuilder? The floorthing and the textures? I´m not really experienced, and im using GZdoom, XWE and, well, DoomBuilder.