moving iTunes from PC to Mac


My partner finally decided to abandon the world of window$ (at least at home). And he asked me to move his iTunes library to his new 20" iMac G5. So I accessed his HD on win through the network and copied his iTunes library to the iTunes folder on the Mac. The problem is that when I opened the iTunes almost all of the songs had the exclamation sign of death.
So we thought that maybe not all of his songs were in that folder and decided to consolidate his library on the PC and move it again to Mac. To do that we changed the iTunes library to the D: drive on his PC (his C: drive did not have enough space to consolidate the library). After the consolidation was done, I shared the D: drive on his Win machine and tried accessing it from the Mac...
the problem is that I cannot see any files after I go more than two levels deep. For instance: D:\iTunes\iTunes Music\Artist\Album\ appears empty in the finder but I know that there are files in there... And it happens with all of the folders on disk D:\
So two questions:
Why exclamation signs appeared after I moved the files on the first place?
Why can't I see the files, which are more than two folders deep from the root of the win share, on the mac?