Is it possible to change the username in Nexus 5?
Is it possible to change the username and passcode without reinstalling UBPorts?
While changing the user isn't supported and not easily doable, changing the passcode is only a bit unintuitive: you have to change the authorization method in system settings to be asked to set the passcode. Not sure how its called exactly in english, but something like that: security&privacy->lock and anlock->security after locking (first item)->choose one of the other two methods and afterwards switch back again... alternatively I guess you could change the code from the terminal issueing
How do I re-install UBports then?
@chdslv Use the wipe option on the installer. It will remove everything though and give you a clean install.