A dropdown tab to enable customer purchasing an item in offering colour or size choice would be great. Or did I miss this?

I am not sure what you mean by drop down tab.
Does the Options list box not do what you want?

Kind of the same box as the choice of how many to purchase.
 
When I add this in a list option list in admin /product it just adds it in text by the side of the numbers drop down tab choice box.

A list box :) To select sizes for product or colour .. now that would be useful anyone know how?

I am puzzled - sorry.
I use options for a product to do what you appear to want.
 
Examples here:
 
http://www.malikstores.co.uk/products.php?category_id=59
http://www.malikstores.co.uk/products.php?category_id=207
http://www.malikstores.co.uk/products.php?category_id=13
 
Is this what you want?

Thank .. yes I finally got it .. though it was not an obvious setting to me anyhow. Thanks & RTFM is applicable to me I guess. BTW I like your pop up box too good job