All in all eReader is clunky (at leats the PC version is). Ia m using this to test t see if i want to buy a Nook.
The two are unrelated. The NOOK doesn't use B&N's Reader software and it works very differently.
If being able to read on a PC or other device in addition to a NOOK is important, then of course you want to check out the Reader software for those other devices. If you're only interested in the NOOK, you need to look at the NOOK instead of the software.
The next update will include an updated version of the User Guide.