Im using amx.1.8.2-dev and yep i just installed and also got some error, both with own compiled and downloaded:
L 07/24/2010 - 12:22

1: [AMXX] Run time error 10 (plugin "amx_super.amxx") (native "get_pcvar_num") - debug not enabled!
L 07/24/2010 - 12:22

1: [AMXX] To enable debug mode, add "debug" after the plugin name in plugins.ini (without quotes).
L 07/24/2010 - 12:41:11: Start of error session.
L 07/24/2010 - 12:41:11: Info (map "gg_33_goodtimes") (file "addons/amxmodx/logs/error_20100724.log")
L 07/24/2010 - 12:41:11: Invalid CVAR pointer
L 07/24/2010 - 12:41:11: [AMXX] Run time error 10 (plugin "amx_super.amxx") (native "get_pcvar_num") - debug not enabled!
L 07/24/2010 - 12:41:11: [AMXX] To enable debug mode, add "debug" after the plugin name in plugins.ini (without quotes).
L 07/24/2010 - 16:17:48: Start of error session.
L 07/24/2010 - 16:17:48: Info (map "gg_buzzkill") (file "addons/amxmodx/logs/error_20100724.log")
L 07/24/2010 - 16:17:48: Invalid CVAR pointer
L 07/24/2010 - 16:17:48: [AMXX] Displaying debug trace (plugin "amx_super.amxx")
L 07/24/2010 - 16:17:48: [AMXX] Run time error 10: native error (native "get_pcvar_num")
L 07/24/2010 - 16:17:48: [AMXX] [0] amx_super.sma::admin_gravity (line 3633)
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