The following Excel items are unsupported in Composer.
A partial list of features are listed below and can be used successfully, but Conga customer support is unable to provide direct support for advanced Excel features.
Array formulas
Images
Excel picklists
Page breaks on an individual sheet
Pivot tables and other advanced Excel features (Vlookups, sumif(s), countif(s), IF(s), Textjoin, and so on)
XML Maps
Text boxes
Using Skip:x in two different columns leads to unexpected output behavior and is not supported. Conga Composer does not support any formula containing (but not limited to) the following functions (see table below):