More CD R/W problems

[Karnevil9]

Let me apologize in adavance for the long post but there is a lot going on here.
My CD burner is Lite-on and the software is Nero express, on a windows XP Pro system.
I have some music downloaded that I wanted to burn to CD. I used a Music CD-R and Nero to burn. It worked fine in my car CD player. I then wanted to add more music to the song list, so I used a CD R/W, Burn the music and again it does fine. I erased all the music from that R/W so I could add a few more songs, this time it doesn't work. It plays on the computer but not in the car CD player as it did before. I try a Music CD-R to burn the music and now a window pops up saying that I have to use a CD R/W disk. I try to burn the music to CD using windows media player, and I get the same message, I have to use a CD R/W and can't use a CD-R. What gives?
I try another clean CD R/W to burn the music and again it won't play in my car CD player, only on the computers.
Anyone have any Idea why it won't play in my car. These are downloaded MP3 files, and I used the create Audio CD selection from Nero which says it converts the MP3 to CD.
Also, why would I get a window that says I have to use a CD R/W and can't use CD-R? Are there settings for this?
I also noticed recently I get a window when opening Nero that says win32 not installed or windows32 not installed, something like that, but it goes away and Nero opens fine. The window doesn't give any more specific information than that.
I recently removed the InCD portion of the Nero install because It didn't seem to have a purpose other than formatting a CDR/W. I think the successful burns were before I removed the InCD, however I have had trouble in the past converting segments of an MP3 disk to audio CD on Nero in while InCD was still installed.