basecomm - Base Communications. Includes features like gag, silence etc.
l4d_ghostpounce_SM1.3 - Just in case you dont know it, need Source Mod 1.3 for it to work, if you use 1.3 and it still not working ask author. Shouldnt interfere with scores.
pounceannounce - something resets max pounce bonus dmg to default 25. Try to remove pounce uncap and set max pounce dmg manually. Shouldnt interfere with scores.
L4Dscores.smx -
most probable cause, since Downtown extension have acces to scoreaboards and this plugins works with scoreboards naturally. Check plugin thread, maybe you have wrong plugin settings.
Hope it will help
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