Hi Matteo - try to make it work with a small range first, eg 10x20. If that works, then maybe it's something related to the volume of data.
Alternatively, in the Queue Reports object on the #Create Performance Report page, there is a code stage called Write Performance Data that might be helpful. You'll need to adapt the code but the technique (to populate an object array that you then write into a range) works well with large amounts of data.
http://portal.blueprism.com/system/files/vbos/Queue%20Reports.bprelease------------------------------
John Carter
Professional Services
Blue Prism
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