Welcome

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Quote: "I want to make simple but fun games. I use Poser7 (and blender but I'm not great with blender yet) for animation / modelling, what format do I need to export the characters I've made in poser into Dark Basic."
.3DS, .x, or .dbo, where .dbo > .x >.3DS.
Quote: "Can I import video backgrounds for the tracks / scenery?"
Yes

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Quote: "What should I get Dark Basic or Dark Basic Pro?"
Definitely DB Pro.
Quote: "I also saw the "3D Game maker" which is very appealing because of its zero knowledge of programming. Can 3D Game maker do what I want?"
No, it's very limited.
Quote: "I want to be able to sell my games. I believe this isn't a problem with Darkbasic. If 3D Game maker is suitable for my game programming and I decide to buy the license will the price of the game or the 1 game license be deducted from the price of the unlimited game license if I decide to purchase the unlimited game license?"
Not sure, but I suggest not getting 3D Game Maker if you want to make any kind of decent game

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