how can i link an object such as graphics on a car without ruining the scripts.

[Rolig Loon]

I'm not quite clear about what you are trying to do.  You cannot "link" a texture.  You can only link objects, so if you want to applay a decal to your car, you either have to apply it to one of the linked prims in your car, or you have to add a prim and texture it. To link prims, simply select them with your Build/Edit tool and type CTRL + L.  Read this quick primer on linking.  HOWEVER, my guess is that you shouldn't be linking anything. 

A script in a complex object commonly needs to refer to the postions, names, and contents of specific child prims.  If you mess with the linkset by adding or removing links, the script may not have any idea which child prims it is supposed to control any more.  If you are extremely lucky, you might be able to get your scripts to respond if you reset them.  Chances are very good, though, that you have broken everything by altering the linkset.  If that's the case, you will need to delete that copy of your car and rez a new one.

I suspect that your car includes a texture change script that is meant for adding decals or changing the paint job.  If so , you should be using that, not trying to add decals by linking prims to it.

[Rolig Loon]

I'm not quite clear about what you are trying to do.  You cannot "link" a texture.  You can only link objects, so if you want to applay a decal to your car, you either have to apply it to one of the linked prims in your car, or you have to add a prim and texture it. To link prims, simply select them with your Build/Edit tool and type CTRL + L.  Read this quick primer on linking.  HOWEVER, my guess is that you shouldn't be linking anything. 

A script in a complex object commonly needs to refer to the postions, names, and contents of specific child prims.  If you mess with the linkset by adding or removing links, the script may not have any idea which child prims it is supposed to control any more.  If you are extremely lucky, you might be able to get your scripts to respond if you reset them.  Chances are very good, though, that you have broken everything by altering the linkset.  If that's the case, you will need to delete that copy of your car and rez a new one.

I suspect that your car includes a texture change script that is meant for adding decals or changing the paint job.  If so , you should be using that, not trying to add decals by linking prims to it.

[Lindal Kidd]

Physical vehicles in Second Life are limited to 31 prims, maximum.  When you added decal prims to the linkset, you probably exceeded that limit, which is why the script no longer works.

There is a cumbersome workaround for this...a few complex vehicles have a "vehicle" part that is nothing more than the sit poseballs and a prim or two linking them together.  Then the driver sits on a poseball and WEARS the rest of the vehicle, a separate object. 

Unless your vehicle includes templates for you to paint your own vehicle textures in Photoshop, your best bet is to contact the vehicle maker and ask if they would create a custom texture for you.