Same here.... Using version 2.00.230. I have only noticed it on Windows XP machines but several of them.
It's really annoying because anytime a large file is created, OS fragments the file around those light blue boxes. I tried variety of methods to clear them out. Chkdsk /R & /F. Windows built in defrag tool. Other defrag tools. Defraggler boot-time defrag. Fsutil. Etc.
Someone please.... At least tell us what they might be.
Thanx