I pointed another slackware user to your original query (they had same problem and same wireless device) - they confirmed the software package the slackbuild creates got his wireless device working:
He followed the slackbuild advice and got this working.
You seem to be experiencing difficulties building the slackbuild so I will attempt to guide you through this - I apologise if it may sound patronising but just trying to lend assistance:
Download slackbuild and source archive files:
and as you have mentioned - you have 64bit system architecture,
Source Downloads (64bit):
YOU MUST BE IN THE SAME Directory as downloaded files, to check at the terminal type "ls":
If you do not see the above items - then navigate to where you downloaded the slackbuild and source archive files
REMEMBER, AS I HAVE SAID BEFORE use the tab key for autocompletion in the terminal - if it is not autocompleting in the context of the present working directory, either the files are not there - or you are not there ;-)
tar -zxvf bro<HIT THE TAB KEY>
and this will appear:
tar -zxvf broadcom-sta.tar.gz
david@slackware13:~/Downloads/src/testing$ tar -zxvf broadcom-sta.tar.gz
now you will see the decompressed and untar'red "broadcom-sta/" directory - use the list "ls" command to check:
move the source archive into the newly untar'red "broadcom-sta/" folder:
mv h<HIT TAB KEY> ./b<HIT TAB KEY>
Change directory into new "broadcom-sta/" directory:
As root user build the slackbuild:
then install the software package you have just built:
installpkg /t[HIT TAB KEY]/bro[HIT TAB KEY]
REMEMBER THE NUMBERS IN THE MIDDLE (are my kernel version) 126.96.36.199_smp- for i486 system architecture - YOURS WILL BE DIFFERENT - and that is all quite fine/normal.
Follow the above and hopefully it has been clear enough
When building the untar'ring and building slackbuild - if you are not sure if you are in the correct directory then just check with the list command "ls" - it will output/show files/folders of the directory you ar presently working in.
From your output/code snippets it seems you're using root to do all this - nothing techinically wrong with that but not recommended for many reasons - it is good practise to be a normal user when possible and only switch user to root "su" when you need be root then "exit" back to normal user - they're terminal commands in the quote marks to do just that - BTW.