Im trying to make one of my active objects become a ladder (rope) but it wont work. I cant just use a quick backdrop because then it cant be used in events (create object at certain time). anyone know how to?
You can only set backdrops/quick backdrops to 'ladders', 'platforms' or whatever. It's one of the many limitations of the built-in movement. What you *can* do is create a backdrop rope and set it to a ladder, then create an active object rope (the exact same image) and just position it over the first one.
On a related note, using a Custom movement engine would be better - there's lots of examples if you want to give it a try.