I have been aware of this limitation myself for quite a while but there is an easy work around.
The problem occurs when the worksheet name includes blank characters (i.e. worksheet named "Sheet1" will not give rise to this problem but a worksheet named "Sheet 1" will give the #Cell'Sheet1'!H8 not named# notice).
To fix the problem simply remove any blank characters in worksheet names. I'll add the issue to my todo list - I'm sure I can get round the problem with a little programming effort.
Please let me know if this fixed the problem for you and thank for reporting the problem in - it all helps the product improvement effort
