Here is an update on the issue. This is a small part of the response to the case that i opened for this:
"What you are describing is a known issue, reported as "CLRT-80263 - Only on MS SQL Database, Action Item Description is truncated when you copy a process via 'Save As' button".
As the title suggests, this is only happening on MSSQL and not on Oracle, that is your scenario. The issue has been reported against 14.2 and 14.3 (probably also present in 14.4) and current status of the defect is that Sustaining Engineering is tentatively targeting this to be fixed for Basie, our next PPM release. I do not have any information regarding any backport plans yet.
I will update you as soon as I have relevant news from Sustaining Engineering regarding this internal case (CLRT-80263) and relate your case to it, I will also leave it open until then."
Thank you all for you feedback