Hi there,
Well done for taking the poor thing in...i have a yemen chameleon myself (and also have kept other lizards for sometime) so if you have any questions please feel free to PM me because i know from experience it can be quite a learning curve.
One friendly bit of advice.....please take the bark out and put kitchen roll in....i know fishworld mean well and good on them for helping you out, but yemens (especially baby's) often mistake the bark for food, try to eat it and unfortunately pass on as a result of impaction. Unfortunately we know of at least one case where bark was advised and provided and this sad situation happened with in days.
If you are wanting to keep him(her?) permanantly, then it might be worth investing in a flexarium (of course this is only my opinion but spent a good while researching the most suitable housing). They are relatively cheap but very durable and perfect for the ventilation that they require.
It might be worth registering with RFUK (reptile forum UK) and having a look round the forum, there are plenty of experienced keepers who would be more than willing to give you advice.
Again its only personal preference, but we purchased our reptiles and equipment from GR8 reps in Rugeley and found them to be very helpful.
Although when reading up about them, they may seem to be "grumpy" animals to keep, our yemen is a welcome addition to our family and is quite a character! Loves sitting on shoulders or heads and climbing the net curtains.
Best of luck to you!