[B]1)[/B] why can’t I use DVD+R discs with Nero 7 to create a DVD data disc? When I try, I get an error message that it’s the wrong format but other software lets me do this. (Nero will accept DVD+R to create back-ups discs.)[/quote]Normally, this is no problem at all. What flavour of Windows are you using?
[B]2)[/B] when trying to rewrite an audio CD-RW disc, Nero won’t accept the disc if I do a quick erase to wipe it first. Is there a way to get around having to do a full (time-consuming!) disc wipe?
Try to quick erase the disc with another tool, ImgBurn for example. If Nero still insists on erasing the disc, then this might be a general problem with audio and CD-RW.
[B]3)[/B] finally, if I want to create an audio disc and only want to have selected tracks without any gap between them, is this possible with Nero?
Yes. Have a look into the documentation.