Confused; struggling to renumber (relayer?) my tab order.

[Eric]

I have a background group in a stack which contains - I hope - all the fields and buttons on the card (some twenty odd).

For some reason, I am no longer able to rearrange the tabbing order as I would wish. Any field, no matter what its number, will only allow me to "Send Forward" or "Send to Front" but the buttons to "Send Backward" and "Send to Back" are greyed out.

However, if I use the Menu Command "Send Backward," the object is actually sent right to the back instead of just one layer.

Lock Size And Position is turned off for the background group and for each object therein. I am editing the backround group. The EditBackground is turned on. The RelayerGroupedControls is turned on.

So why are two of the arrow buttons greyed out (indeed why only two - with two working)? And how do I get all four relayer buttons working again?

Thanks for your advice, you old-handers.

[Eric]

Actually, I have just discovered that, greyed-out buttons notwithstanding, I CAN actually change the object numbers/positions - by typing new values into the layer field of the "Size and Position" object Inspector.

I cannot type new values into the number field, for some reason (greyed out); but, when I type a new value into the layer field, the number I type becomes the object's new number - whilst its "layer" stays unchanged.

I am more than a little confused about the difference between an object's "number" and its "layer."

Can anyone explain to me:
1) the conceptual difference between number and layer;
2) the reason why I am unable to alter an object's "number" but can type data into the "layer" box;
3) why doing this then alters the number and NOT the layer?

4) my earlier question - why are two (and just two) of the relayer arrows greyed out?