download them from garrysmod.org
No it is not. It requires one of the games in the half life 2 series such as TF2 portal or half life 2.
go to www.garrysmod.org there are free addons for Gmod, just search for tf2 or team fortress or you can get a friend on steam that's tf2 and ask him to email files: D:\Program Files\Steam\steamapps\hisusername\teamfortess2\teamfortess2\materials and D:\Program Files\Steam\steamapps\hisusername\teamfortess2\teamfortess2\models
you cant unless you know something i dont actually it is possible to make an underwater base but not in gmod. you can use the hammer editor to make a map then add water to it and take out the water in the parts of the map where you dont want it. if you have css you can map it with that and i thing you can also map it with tf2. there might be other source games which you can map it with but if there are i don't know about them. and once your done making the map you can export it the which ever game you used then play it on gmod. hope this helps!
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download them from garrysmod.org
No, you do not need counter-strike to play gmod. I don't even have counter strike but i do have gmod. A word of warning though, a lot of the materials and weapons in counter strike are used in garrysmod. Mostly in mods, and maps. It is recommended to have it.
Try reinstalling the game, especially TF2 since it is the game containing that file. HL2.exe happens to be the main executable of the game. In other words, it's a necessity.
No it is not. It requires one of the games in the half life 2 series such as TF2 portal or half life 2.
Video card, depends on your system. I reccomend NVIDIA brand.
You need a source gam like HL, HL2, TF2, or Left 4 Dead. If you have one and it still won't work then you should ask elsewere
go to www.garrysmod.org there are free addons for Gmod, just search for tf2 or team fortress or you can get a friend on steam that's tf2 and ask him to email files: D:\Program Files\Steam\steamapps\hisusername\teamfortess2\teamfortess2\materials and D:\Program Files\Steam\steamapps\hisusername\teamfortess2\teamfortess2\models
I think you can use portal in gmod 10, but I'm not so sure.
you cant unless you know something i dont actually it is possible to make an underwater base but not in gmod. you can use the hammer editor to make a map then add water to it and take out the water in the parts of the map where you dont want it. if you have css you can map it with that and i thing you can also map it with tf2. there might be other source games which you can map it with but if there are i don't know about them. and once your done making the map you can export it the which ever game you used then play it on gmod. hope this helps!
Yes, you must.
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If you want to make models for gmod look at XSI Mod Tool.