Ignition 7.8.1: Malformed format string executing report

Hi,
I have this very simple query:
[attachment=3]qry.PNG[/attachment]
From the Key browser I drag the query datasource item onto the report page and then the IDComponente field into one column. My final table is:
[attachment=2]table.PNG[/attachment]
When I try to preview the report or I try to see it on a page with a ReportViewer I get the following exception:
[attachment=1]exception.PNG[/attachment]
Any attempt to set the Number Format property of the column fails with the following message:
[attachment=0]exception2.PNG[/attachment]
If I run the query in SQL Server Management Studio or in the Ignition Database Query Browser I get the expected results.

Any suggestion?

EDIT
I cannot even add a textbox to show the page number with the @Page@ Built-in key: as soon as I do it, I get the above exception. The only fields I can show are text and datetime field. No int, smallint, long field is accepted.

EDIT #2
I saw here:
https://inductiveautomation.com/forum/viewtopic.php?f=94&t=15177&p=55742&hilit=malformed+format&sid=ab04ee898bf7714ff1dd60f8220132b8
that this is a bug in 7.8.1, which was solved in version 7.8.2.
Since I don’t want to update to 7.8.2, how can I get onyl the reporting module? Is it safe to update this module, i.e. will I loose my Ignition activation?

EDIT #3
Just updated the reporting module: it works