Yes, you can create the launcher you need.
Fist of all, my Ubuntu is in Spanish, so I will translate some words; I hope you understand me.
1.- Create a proper script that run the Bricscad script.
Open gedit and write this:
Save the file into your personal folder (/home/your_user_name) with the name .run_cad.sh (the fist dot hides the file, only if you want to hide it).
2.- Create the launcher.
For Unity: Press the Super key (that one it usually has the MS Windows logo) and write Main Menu (this is my translation from spanish). So, you will find a program to create launchers. Select a menu, for example Graphics, and then click on the New Item button. Select an aplication type, choose a name, an icon, a comment, and for the command option write sh .run_cad.sh.
3.- Create a Unity launcher (optional).
If you want an icon on the Unity launcher, look for your app using the dash, and then drag it and drop it over the Unity laucher.