[Austin]

The sma is the source code for the amx plugin. It has to be compiled.
For my installation I have:
Sierra\counter-strike\cstrike\addons\amx\examples

1) Put the sma file into the examples folder and then run the sc.bat file.
It will compile all of the sma files in the example directory into .amx files.

2) then put the amx file into
Sierra\counter-strike\cstrike\addons\plugins

3) Edit the
Sierra\counter-strike\cstrike\addons\plugins.ini
file and add the line:
awpdrop.amx

I am using awpdrop, not awplimit. I never tried awplimit.
As I said before awpdrop works very well!