works for me...but as I said...maybe your storing method is different.
So, I've created an empty folder e:\temp\test and put the rar file in it.
I went to dir2dat, settings can be seen in attached screenshot and hit create....and it created:
<machine name="abra ca dabra (gottlieb)(1975)">
<description>abra ca dabra (gottlieb)(1975)</description>
<year>
?</year>
<manufacturer>
?</manufacturer>
<rom name="1.00\abra ca dabra (1.00) screenshot.jpg" size="225870" crc="8662079b"/>
<rom name="1.00\abra ca dabra (gottlieb)(1975)(popotte)(1.00).fpt" size="10844160" crc="47349cbd"/>
<rom name="1.00\abra ca dabra readme.txt" size="973" crc="a69481a5"/>
<rom name="1.50\abra ca dabra (1.50) screenshot.jpg" size="338280" crc="167a71f3"/>
<rom name="1.50\abra ca dabra (gottlieb)(1975)(popotte)(1.50).fpt" size="10896896" crc="84d5d662"/>
<rom name="abra ca dabra flyer.jpg" size="1886951" crc="5c94115c"/>
</machine>