one problem is you have too many modules installed. You have ALL of the cloud modules installed into a single machine.
I've turned off all of the cloud modules. They are not what you want. amongst the cloud modules there is a module for controling which server processes get directed to and many other features to allow multiple servers to serve a single website to allow it to scale to a massive scale.
You dont need any of them, suggest deleteing every module in the 'cloud' category as you are on shared hosting so they are just thowing errors.
You also have a very old version of site builder installed but not active, suggest deleting all modules under the 'site builder' category in the ACP.
Your site is very slow to navigate around, suggest better hosting.
Dont know why your system wont allow /plugins/ to be used as a profile name.
I changed it to
http://dubmusic.com/plugins1 and it worked ok.
My guess is some server settings are protecting that name because of some other system like wordpress or other where that is a common attack point.
Could ask your server company, or use a different server company.