[An Mds file and also an extra folder while extracting the ISO using WINRAR]

Hi

I am creating ISO for my project which has installable components and jars etc..  - i made the project files as as Disk-1 [1.3GB] and Disk-2[620MB] .. When Disk-1 ISO is made it is single iso file and when I extracted using ISO then the folder structure is -

Lets Imagine vk.iso is ISO name and c:\test is the location where ISO file is generatedwhere as ISO has files Disk-2/Folders related to my project <ISOName>/<Myproject related folders> that i gave for iso - Whne I have extracted then Foldeer structure is vk/DIsk-2/<Myproject related folders>

where as when I make ISO using ImgBUrn  using ISO9660+UDF then I see two files created - An ISO file and an MDS file of size 5kb.

My first question is why an mds file is generating where as in case I for Disk-1 its not...

when i extracted  using wINrar THEN I SEE vk\ISO\Disk2 - I see an extra folder called ISO ....why it is getting generated....

 

Note:

I have tried the settings 

FileSplitting - 780MB in Read and Build Tab

 

Please help me why i am getting an mds file and also an extra folder - ISO while extraction