Paragon B&R Home 2012 - files missing from restore view

I created a backup from a USB stick and chanced to examine the archive afterwards. One particular source directory ('Documents') contained 3 subdirs and 9 files. In the Restore view tree control, where you select files to restore, only the 3 subdirs and 3 files were visible. One .doc file, one .jpg and 4 .txt files were missing. When I restored the whole directory, all the files were there.
This was on WinXP 32; I also examined the archive with HDM Pro on the same machine with the same result and on Win7 64 with HDM Suite 2012, again with the same result.
No includes/excludes were in effect.
If I mount the archive as a drive letter, everything is there. It seems to be a cosmetic problem with the tree view, but not being able to select individual files is a pain.
Any suggestions appreciated.

Edit: further to the above I repeated the original procedure on Win7 using HDM 2012 Suite and got the same result - 6 files missing in the tree view. I then tried copying the USB stick to the hard disk and doing a File and Folder backup with B&R Home and this time all the files were visible and could be individually selected. Weird.

bob