Bondas25, Half life 1 costs less than $10 in some countries, or you can find them for a bargain over some sites!
The thing is the ESF community does NOT give support to non steam players or won players, what means whatever question you got about esf, you will find yourself alone in this forum.
make a quick buy of half life1 in steam and you won't even have to wait for the cd, you can download it from steam servers at max speed, run the game once and install the mod.
Quick, Simple and Clean. Plus you get lots of support from esf community