I'm on Kubuntu 15.04, which was upgraded from 14.10.
My autostart menu shows 3 programs and 1 script (ksuperkey enabled, pidgin disabled, steam enabled and my nvidia_fix script). Those were migrated from 14.10, but I'm pretty sure that I also had one more script there - that fixes some chrome bug for me.

Anyway, when I add a new script, it shows on the list, but after I hit Ok (apply is grayed out) and run the autostart manager again, the script is not on the list. I can also verify that not only is it not visible, but it doesn't work.

If I try to add the same script again, I get a message box, the the file will replace itself, and that I should provide a new name. If I cancel this message or provide a different name, the original script is again visible on the list - but it will vanish once I close the autostart manager and run it again.

Reproducible: Always

Steps to Reproduce:
1. Add a script to autostart
2. Click OK after it is added and visible on the list
3. Run the autostart manager again

Actual Results:  
The added script is no longer on the list.

Expected Results:  
The added script should still be on the list.

I'm not sure if the one script that survived the update to 15.04 is even working. It was a script that fixed graphical tearing for me on 14.10, but now the tearing is back.

I can see that the scripts I try to add ARE in ~/.config/autostart/ , but the one script that did not migrate from 14.10 is shown as a 0 byte file, and the new scripts I add are there looking OK.