Re: custom Tab not appering when distributed as addin
The reason the tab sometimes appears is due to the file containing both CustomUI and CustomUI14 sections.
If you open the file in xl2007 the tab will appear.
If you open the file in xl2010 or newer it will not. This is because excel detects both CUI and CUI14 sections and uses the CUI14 one, which has no xml code.
You can use the editor to delete that section and then it should function on all versions from xl2007 to latest.