Error invalid cell EPM functions

Hello,

EPM 10.0 SP17 - v NW

I have a report with following function EPM on a cell

=EPMExecuteAPI("OpenSpecificDocument";"Open BP template";"REPORTS\TEMPLATES\test\BUSINESS PLAN.xlsx";"")

This function open a new report of my server. It´s perfect. But when the report has lost the focus, my others EPM functions show in the cell the message "Error Invalid cell".

For example

=EPMCellContextDocument(1;INDIRECT("$AF$8";1);"Upload document";;;$B$13;$C$13;$B$4;$C$4;$B$14;$C$14)

This function EPM open my content library. Then when I execute double click on EPMExecuteAPI... open new report. Then come back to my original report and in the cell when I have the function   =EPMCellContextDocument(1.... ,

Cell shows "Error invalid cell." Any sugestion?

Thanks

Gustavo