Nope - it starts in there as it should. Open console by ~ key(or ESC in main menu) and write "map c0a0" (without brackets), this will boot you up in the first map.
Yey, an old half-life!
Had a good time, thanks.
Btw i decided to test various GoldSource console commands and wrote "thirdperson", then "cam_idealdist 100", and look who's there:
http://steamcommunity.com/sharedfiles/filedetails/?id=675724767
Then i wrote "cam_idealyaw 180" and hid the weapon...