judging from the size of that lamp, it seems a little small overall...unless your cham is quite young (but if so, expect her to outgrow it pretty fast).
you should realize that with a free range, unlike a cage, you can not simply make it smaller and still expect them to stay within its confines. honestly the only real test is to *strictly* monitor them the first week or so, and if they are wandering away from their free-range, then it is most likely too small for them.
Needless to say, it will need to grow as they grow....and assuming you have a relatively young cham, get ready for those growth bursts sooner than you think
(suggestion: go up not out)
EDIT: I'm not sure what that little tiny plant is on the ground, but I don't imagine it will serve much purpose (as far as your cham is concerned). also, in my experiences, they love to climb onto the lights and
THEY CANNOT TELL THAT THEY ARE BURNING THEMSELVES. From your third picture I would be very concerned about her climbing down to the ground, over to the cord of the light, and back up to the light, burning herself (esp if she's younger the damage can be more severe)
