I'm tagging a m4 carbine (my first time) and I got the nodes and the markers on the right place but I don't know how to link them. Any help would be nice.

I don't know anything about weapons, but I know how to link things. Select the thing you want to link to another thing, click "link", then go to "select by neame" (next the select), and link it to whatever you want to link it to. Hope that helped.

ya didn't really explain it that goodly

lol
OK. Go to "select by name". Click on whatever object you want to link. The click on "select and link" (there are buttons named like this). Then click on "select by name" again, and click whichever object you want to link it to (the frame). This time, instead of saying "select" at the bottom, it will say "link". Click "link". Not to get out of "select and link" mode, click on the regular select tool. Now the "select and link" button should be inactive. Now you're done. When you click on "select by name" again, the object you linked to the frame should show up under the frame as a sub directory thingy (if the "show sub directories" check box is checked).

Alternatively, you can just click "select and link", click on your object, then drag it over to the frame. That sometimes works.