1.) Here are some examples. Shown at the left is the 3 elements I'm trying to align vertically and horizontally. Example 1 shows what happens when I select the elements and click the "Horizontal Align Center" button (dashed outlines show initial position of stacked elements). Example 2 shows the same issue when using "Vertical Align Center".

2.) Group it to what? Itself? Grouping the symbol to anything (or itself) no longer gives you the option to unlink it (unless you isolate the group which defeats the purpose).The symbols themselves were created with groups (and sub-groups), and in CS3, those groupings were retained after unlinking the symbol. Your response doesn't actually make any sense.

No mask on the image.

Snap to pixel grid is not on.

Tried following your instructions to "group the symbol before unlinking"? Yes. I placed a symbol on the artboard and hit ctrl+g to group it. Then right-click and the option to "Break link to symbol" is no longer available... I can isolate the group and then break the link... This doesn't actually solve anything, it's no different than unlinking and then grouping the still-selected elements back together, which is something that didn't need to be done in previous versions of Illustrator. Besides, in some of my symbols I have fairly complex sub-groups so that once the link is broken I can adjust individual groups of elements as necessary (at least that's how it worked in CS3), but now, breaking the link completely explodes the symbol into it's component elements so I have to go back in and re-create all the subgroupings which is time consuming.

This also does not solve the sub-layer issues which I recorded below. There is no audio, but here is a description of what occurred.

1.) Several layered background elements on artboard (all on the same/current layer)

2.) Placed symbol from symbol library (again, on same/current layer as the other elements)

3.) Break link to symbol

4.) Group symbol back together

5.) Select all the elements and alt+drag/drop to create a duplicate.

You can see that the duplicate symbol is now BELOW the other duplicated items, and this is because the symbol is in a sub-layer which I tried to show in the layers pallette... So, now if I want to bring that symbol to the front again, I either have to copy it and paste it back into the same layer I'm already working in, or I have to find the damn thing in the layers pallette and drag it out of the sub-layer. Both of those options are a pain in the ***. Also, since the unlinked symbol is typically selected once I've unlinked it, anything else that I create ends up in that same sub-layer and results in the same problems.

Yes, I can use the symbol panel to unlink the object... I'm not really having trouble unlinking the symbol. I'm having trouble with it being exploded and losing all the sub groupings as well as being placed in a sub-layer that doesn't play well with all the other elements on the artboard.