Box update - the plan

Now I have a much better idea of what I want and how I'm going to go about it now. 

I'll try to add photos so that you can follow my waffle a bit better, but until then ...

The box as it is now (see photos here):
The box is cylindrical.  The lid drops into the body of the box, rather than drop down over the outside of the box.  Now, so that the lid doesn't fall right into the box there is a thicker part to the bottom 2/3 of the box and the lid sits on top of this.  So I have the space between the bottom edge of the lid and the bottom of the box to play with.  When the box was bought it contained some lovely toilettry bottles and these were kept in place by a circle of thick card with holes in it for each of the bottles.  This was held up from the bottom of the box by a strip of similarly thick card, which 'propped' it up (as a result, the bottle bottoms dropped down through the holes to the bottom of the box and the upper half of the bottle 'peeped' out of the circles cut in the larger cirle. With me so far?

The science bit (now concentrate!):
I want to separate this space into two and make a lift-out tray, so, I've measured the depth of the box (before the stop for the lid) and I'm going to use the strip that came with the box as the sides for the lift-out tray.  So, depth of box below 'lid-stop' minus depth of lift-out tray equals the depth of the comparment in bottom of box (or the depth of the strips I need to cut).  Are you following?

The plan is that I'll insert a double thickness of card around the inside of the box as a 'stop' for a removable tray (so it won't drop to the bottom of the box).  Now, I have a question/query about this.  The intention is to cover all these bits of card with velvet.  The card I bought isn't as thick as the original 'innards', so do I a) use a double thickness for the 'tray stop' then cover with velvet, or b)  would be that the thickness of the velvet be enough so that I only need to use one thickness of card?

Once I've cracked the 'lid-stop' I'm going to use a circle of card, glue a thin piece of upholstery padding to it and cover it in velvet.  Then this padded, velvety circle will drop (I hope it will be that easy) into the bottom of the box.  And hey-presto - I'll have finished the bottom compartment of the box.

When all this is done, I can move onto the 'lift-out tray'.  My plan is to use the innards that came with the box for this.  I'm going to stick the strip to the edge of the card circle (which I may replace with a new circle as the cut-outs in it may cause a bit of an issue).  I'll probably use something like a 'papier mache' technique of small pieces of paper to glue it at right angles to the circle, little by little.  I'll probably add a circle of padding to the tray before covering it too.

Now, for the covering.  I guess it would look best if I cut a strip of velvet that is wide enough to cover both the inside, edge and outside of the tray edge and sew it to a circle for the inside of the tray.  Then, carefully glue it to the inside of the tray, over the edge and down the sides, before hand-stitching the bottom circle to cover the underside of the tray.  PLEASE get in touch if you have any better suggestions.  This bit is scaring me a bit!!  If I remember (!) I hope to add a couple of small loops to the inside/top so that the tray can be lifted out easily.