There is a problem with the field lengths in the project database and extract/import from/to spreadsheet.
ACAD attributes allow 255 characters.
Many components have restricted field lengths in the database.
When one has a spreadsheet and is editing it for import, one potentially has no idea what the field length limit is for a given column of data.
I have been using ACE for a 6+ years now and must admit I don't know the field limits for many of the required symbol attributes.
I have been looking and am having a hard time finding this data in the help system, or even on a simple google search.
Solution:
Add the field length limit notation to the first row for changeable items, those without the "( )".
Possibly ATTRIBUTE_NAME=FIELD_LENGTH, or some other delimiter other than "=" that works.