[Maxximou5]

It's complicated in that aspect regarding CS:GO and trails, the only proper usage is using: TE_SetupBeamFollow
You can try out different sprites if you wish, just modify line 33 in the source file.
Search the pak01_dir.vpk in the section: materials/sprites/*
There are complicated methods of using custom ones, this free version does not nor will it use custom sprites.

Also for future readers, I am aware that if you stop moving and the beam fades away, it does not return without doing the command again. That is why I incorporated the spam check command for how many times per round someone can do it. This is to ensure no one spams it and uses too many.