Word of warning abut working with transparent mixes...

If they are not showing content and locked - ie 'invisible' and you enable the layers preview or libraries, for example, you will be able to see the whole of your control window (layers preview or libraries, for example) as oposed to it being obscured by mix windows.

However, if you try and click on a control than actually resides UNDER a transparent mix window (with no content in) it seems that the control doesnt respond!...

This is because the control is being displayed UNDER a transparent, locked, mix window....

Solution: move the (layers preview or libraries, for example) to another part of the screen, not populated by invisible mix windows...

Simon