Yeah, you should be able to find the information you are looking for here in the forums using the search function.
Try searching for decompile for example.
bsp to map?
Ive tried the seach function but it turns up almost every topic on this level design forum.
I HAVE tried this with numerous phrases.
I’ll continue trying I guess.
Boleth, I haven’t decompiled any bsp myself, but this thread seems to have the info you need:
http://www.splashdamage.com/index.php?name=pnPHPbb2&file=viewtopic&p=30665
Hope that helps.
Boleth, honestly, IF you would do what we are saying, you would have already decompiled about thousands of maps. Click the damn smiley in my last post and READ the thread. ydnar posted some examples for a batch file. Its for Q3, but ET is the same deal. :bored:
In the thread eRRoLfLyNN posted is an example batch file for conversion. That should really help you out.
k thank you
I did multiple searches for “decompile .bsp to .map” and numerous other like it.
Im sorry but it just kept listing almost every topic on the level design forum. try it!
thanks errol
much appreciated
No problem 
Just a tip about searching, if you write the word “and” between the words you’re searching for, it should bring back fewer/better responses eg “decompile and bsp and map”.
Good luck!
"C:\Editing Tools\GtkRadiant-1.5.0\q3map2.exe" -convert -format map -v -game et -fs_basepath "C:\Editing Tools" "C:\Editing Tools\KOTH.bsp"
Ok got it sorted
Im just gonna leave the code here for anyone searching the forum for how to decompile a .bsp
I didnt have a clue how to use q3map2 before hand and it was difficult but I got there.

sorry for being a pain in the ass.
Thanks again guys couldnt have done it without you.
I will just add for anyone searching for how to decompile a .bsp that you need to enter the -game syntax for et and rtcw (maybe others also) and that you enter the above code (with appropriate folders) into notepad and add .bat to the end of the filename.