I am a current reseller and I have custom nameservers on my domain so since I am transfering my domain to cpwebhosting.net. will my custom nameservers still be active or do i need to reset them up… and if there not setup will my customers have down time?

First of all take the temp nameservers of current company then make own and change it to your domains.

The IP addresses won’t be the same, so Your nameservers will be obviously reset.

The ns1.domain.com will stay on your client’s domain ns pointers but you will have to recreate the nameservers after the transfer.