Having issues connecting to management interface over network with m4100 (GSM7248p)

Finally, after much tinkering the past few months I finally decided to go up to our business at night while we were closed so I could take the network offline and do some real testing, and after much frustration, I have finally got it to work correctly as expected. To anyone having similar issues this is what I had to do:

Download the text config startup file from the switch to my computer. I then opened it in a text editor and scrolled to the bottom of the file and saw some interface configurations like this:

interface vlan 1 
routing
ip address dhcp
exit 
interface vlan 20 
routing
ip address 192.168.116.12 255.255.255.0
exit 
interface vlan 10 
routing
ip address 10.0.20.24 255.255.254.0
exit 
ip management vlan 20
exit 

Since I am doing only L2 switching there was no need for routing. I deleted all those (but still left the global config set to disable it) and then completely deleted the vlan10 configs. the bottom of the file now looked like this:

interface vlan 1 
routing
ip address dhcp
exit 
interface vlan 10 
routing
ip address dhcp
exit 
interface vlan 20 
routing
ip address 192.168.116.12 255.255.255.0
exit 
ip management vlan 20
exit 

I then uploaded it back to the switch, gave it time to load the new configurations and whala! Alas, success! It makes sense after checking that file but I still feel there is an issue with the way the web GUI makes configuration changes. Technically it should of still let me connect to the GUI with the 10.0.20.24 still configured to VLAN10 because I had set the mgmt vlan to VLAN20, not to mention I could ping 192.168.116.12 all along so I know the switch was aware that IP address belonged to itself somewhere. Also, the webGUI does not let you (that I could tell) simply delete a ip configuration on the management interface configuration page. It will throw an error if you attempt to leave it blank. So anyways, I will now only use the CLI to program this switch because it seems the GUI does not have full capabilities. If I am wrong about not being able to delete a mgmt interface config from a vlan altogether, someone please correct me.