As for the quick reply it is enabled by default but apparently u r either using vB3.0 or it is disabled (more likely disabled)
so if you are using 3.6 and above go to the AdminCP > vBulletin Options > Message posting and editing options > Quick reply ====> Yes, Click not required
thats the best choice when u enable it
if you have that enabled then it must be a template problem thats preventing the quick reply from showing, go to AdminCP > Style manager > edit templates > find the template postbit_quickreply or something like that and revert it so it goes back to default (this is in just a few cases and its rare)
and as for the legend there are several ways and the best one was adding CYB's Visitors in the last X hours and can be found in the CYB pack for 3.7 by hoxxy
search for it, other ways are available but they are a lil unprofessional in my opinion, the CYB's is professional and easy to use via the adminCP