i dont know which bot u dled. But dl this one here
http://www.redsaiyan.net/filedb/filedb.php?action=file&id=28 , click on that , then go to download this file , then once uve downloaded it do this.
1. Put esf-bot.dll into the dlls directory , which is usually C: \SIERRA\Half-Life\esf\dlls
2. Open notepad then , when ur here.. C: \SIERRA\Half-Life\esf , drag the file liblist.gam into notepad , then once uve done that replace gamedll "dlls\hl.dll with gamedll "dlls\ESF-Bot.dll
3. Now join an esf game , then once ur in, press ` and that should open up console , once uve done that type in addbot. To add as much bots as u want without having to type it again and again just press the up arrow then enter , then up arrow then enter and just keep doing that till theres enuff bots , hope this helps.
btw i put spaces in the C: \ in between the : and \ cuz it would do a smile , so if u would backspace that and get rid of the space thats in it , and ur all set :]