Buy the game on Steam (it is often on sale for $2-5), download it once, then use Steam > Go Offline . This gives you 100% functionality, guaranteed security, and the ability to play all the great mods from GameBanana.
Even the "top" downloads have problems. Here is the fix list:
: Historical and DRM-free versions of the game can be found on Internet Archive ValveArchive Technical Specifications
Since you are playing offline, you will need bots to play against.
Avenida São Borja, n° 2181 - Prédio A - Fazenda São Borja - CEP: 93035-411
São Leopoldo - RS - Brasil
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