v0.9 release notes:
You'll need to move your cheats.txt file into the cheats directory. This version can access any cheats files in the cheats directory by highlighting "File: ..." and pressing left/right. They're in the order of the files in the directory, so make sure you copy the file you want to come up first into the directory first.
For tips on using Construction Mode, see this thread.
When you enable Construction Mode, it doesn't become fully active until you close the menu screen. Use the arrow buttons and analog stick to move around. You can move faster by holding X. It can be easier to see what you're working on if you use L1+LEFT to zoom out.
Here is a list of known object IDs. Objects usually take a couple seconds to appear. If you move too far away from where the object was originally created, it may become invisible. Holding R1 will usually make it appear again.