Missing folders when exporting from WLM 2012

I am trying to make a backup of my WLM emails, using the export and import feature described on these boards.  It all seems to work except for a few folders.  When I look at the files that were exported, they are organized into the following folders:

<Bestweb (qu 670 - (Bestweb is the name of my ISP but I have *no* idea to what the following letters and numbers refer)

     <Deleted Items

     <Drafts

     <Inbox

<Outbox

<Storage Folders

     <Deleted Items

     <Drafts

     <Imported Folder

     <Sent Items

However, these are not the only folders that I have in WLM.  I have copied a screenshot below of my folder organization in WLM and many of the folders are missing, including the 'Sent' folder and everything from '60th b-day' to WC-receipts'. 

Under the IMAP tab for this email account, I have the following settings:

Folders:

  Root folder path: Inbox

  Check for new messages in all folders: box is checked

Special Folders:

  Store special folders on IMAP server: box is checked

  Sent Items path: Sent

  Drafts path: Drafts

  Deleted Items path: Deleted Items

  Junk Path: Junk E-mail

Any idea why many of these folders are not being exported?

Thanks for your help.

PS I have the latest version of WLM and am using Windows 7 Pro.