I'm getting the following error when attempting to create a repository.
An IP address (ending with .253) is created for the repository in your PXE IP address range. This address is clashing with something else. Your PXE IP address range needs to be totally free for KID.
Are you creating multiple repositories? One possibility is that you are trying to create two repositories in the same subnet with the same PXE IP address range... this won't work... in fact it is better not to have two repositories in the same subnet at all, but if you must do it, then they should have different PXE IP address ranges and they both can't be active at the same time.
The other possibility is you have some other equipment which is using IP addresses in your KID IP address range. The whole /24 subnet needs to be dedicated to KID. KID can use any /24 address range as long as it is not being used by anything else. Note: You don't need a gateway for this network. It will only be used for local traffic between the Repository server and the machines being imaged.