Hello everybody. So, when i was young i used to play total annihilation with my dad, but then i lost my cd's. Many years have passed and i decided to search on the internet for some downloads and then i found this site, and it's just awesome. So, i want to buy the "Total annihilation: commander pack" as a gift to my father, but i would like to know somethings:
1)The games are up to date?
2)It features all those units that are available to download or i have to download it on another site?
3) I can install it as many times as i want?
4)I can install it on two machines and play via lan?
So, i guess that's it, thanks a lot!
ps: sorry for my bad english.

1) up-to-date, yes.
2) So far as I know, it has all of the Cavedog maps / units / features.
3) You can install it for your use only as many times as you want.
4) See above. I don't know about the technicalities of playing via lan, but your dad will need to create his own account so you can gift that second purchased copy to him. The site doesn't let you own two copies of the same game in your account, though you can have unredeemed gift codes in your account for as long as you'd like.

Here's a thread that explains the gifting process: http://www.gog.com/en/forum/general/how_does_one_make_a_gift_aka_gifting_on_gog_for_dummies

Have fun playing this classic with your dad!

If I recall correctly, disc 1 can act as a multi‐player spawn CD—I think it’s implied that you’re free to use a single licence for LAN‐play.

I stand corrected. If that's the case, and if that option still stands with GOG's release, then happy LAN gaming!

These things with the old games can get a little weird in the age of digital distro.