You need to made some changes inside the loop.
First- your i variable
returns zero all the time, you rather need to use count variable
when offsetting.
Second- instead of offset I would suggest to use Cells()
reference like presented below.
Proposed loop could be as follows:
'...your code here
For Each ws In ActiveWindow.SelectedSheets
count = count + 1
ws.Name = nmRange.Cells(count).Value
Next ws
'...your code here