New Mapper/Scripter - Info?

[Gamemakingdude]

Hi, I'm gamemakingdude or GMD for short.

I've just recently discovered the hpl2 engine and i think its a pretty awesome tool. I'm often having problems with the .lang file (i need help with getting notepad++ set up for .lang)

I'm currently making an custom story but i'm having lots of problem with the mapping (like overlapping floors, thin ceilings, parts of the wall missing (as in see through them) A glitching lamp (Don't ask...))

I'm ok with the scripting part and i can learn scripting pretty quickly.

Any information would be heaps awesome and any tips as well.

[EDIT]

What is a typical size for one map? Also if you use a custom enitity do you put it in an entities folder with your custom story?
PS

Yes i look at the tutorials and the scripts functions on the wiki