Hi Chiara,
Looks like you got some answers about your edema, sorry I couldn't get back to your last email, but obviously we have more important things at hand!
How do you have her laying tub set up? The container needs to be at a MINIMUM as deep as she is long (including tail). I personally have found play sand (fine and clean) which you can get Home Depot for a few bucks a bag mixed with coco-fiber works great. Getting the right consistency is crucial so her tunnel does not collapse on her. The sand helps to hold everything together. It should all be moist (not wet) enough so if you stick your finger in that it will not collapse after.
Obviously if she is this close to laying you can't be making a lot of changes so I hope what you have is sufficient. My way is certainly not the only but it what worked for Luna.
Has she dug any starter holes and then abandoned them? Chams vary - Luna would ignore her tub until the moment she was getting to dig and lay. Other r keepers have chams that wander and dig for several days before settling in. However, the abandoning of holes could also be that she is not happy - this is not good, b/c if she is uncomfortable with the setup she could become eggbound - Don't panic, it is early yet 
Can you post pics of her setup? I tried to keep a 40-60w regular bulb on the tub to keep it warm, just be careful not to dry out medium. Don’t worry about food (hopefully no stray crickets in the cage - if so, put in a piece of carrot for them to munch on. When she comes back up is she basking? Does she seem “normal?” More important than food right now (she’s got plenty of things taking up space in her belly!) is water. If she will take water (dripper or however you give) and keep humidity up if you can. If she is spending the nights in her branches, she is not quite ready and may just be checking out what you have provided.
Once she goes down and digs, and digs and digs you will know. Eventually you will see her turned around in the hole, which means she is laying. When done, she will come out, cover the hole and return to her branches – thirsty and hungry. Offer her food, but she may not take it for a day. She will likely look like an abused and neglected animal – the difference is amazing (see below). The time it takes varies. Luna usually went down late afternoon, dug and lay at night and was up in her branches the next day.
ChamNews has a great article on a laying setup: www.chameleonnews.com/year2003/jan2003/nesting/nesting.html
Here are some photos of Luna before and after, her laying tub. You can go to link for other pics. Hope this helps!



Luna gravid/laying
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Chameleon Help & Resource Info
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