Webpanel GUI for Clients throwing 500 error.

Trying to access the Client area on port 2083 throws a 500 area. How does one fix the perms for root files?

you probably have expired cwp files, try checking if your cwp is updating as cwp files for security reasons are valid for a limited time.
if you stuck you should contact cwp support from the website

there is a problem with the panel (2083) inputs.

-Panel does not open at all.
-Panel opens late / slow.
- Even if the panel is entered, no action is taken.

you probably have expired cwp files, try checking if your cwp is updating as cwp files for security reasons are valid for a limited time.
if you stuck you should contact cwp support from the website

- It gives an error when entering the panel.

http://prntscr.com/w83rza

- After adding a new user, the user panel (2083) cannot be logged in, after saying log in, it redirects to the login screen.

can you check the log ?

Identified the issue was with not having a theme selected under User Acounts>Features,Themes,Lang>Themes