Thanks for the extra pictures. That helps. Here are my thoughts:
- Chicken wire is unusual for that type of enclosure. Are you sure it is chicken wire (hex-shaped) and not diamond-shaped fencing? Chicken wire is too weak and diamond fencing is too large which is why hardware cloth is generally recommended for protection. If diamond fencing was included, it will likely have better attachments than zip ties which will degrade over time and eventually break. I'd put up to the diamond fencing as a backer to the hardware cloth to help hold it in place.
- I don't see anything that you can anchor a padlock or even carabiner to for a strong lock. Maybe you can get a good metal ring below the u-latch that you can somehow lock to the u-latch. Possibly someone else will have a better idea. The hardware cloth there will not be strong enough to be a permanent solution if you mount the lock directly through that wire to hold down the u-latch.
- The gap around the door is large enough for a raccoon to grab a chicken and kill it. I don't have any good suggestions on how to stop that.
- It is frequently recommended that you have a 1ft "skirt" of hardware cloth around the base of the enclosure, either buried vertically into the soil or just below the surface. This will discourage digging.
Unfortunately, chicken coops/enclosures are very attractive to predators. That is why we must setup as close to a Fort Knox protection system as possible. The basic structure looks good, but it does need some tweaks to give you the best security. Good luck.