hi Lino,
sometime ACT_UPG phase stuck due to memory, Please have a look at this note. It might be helpful
1387739 - Out of memory errors during shadow system operation
Please download latest TP patch and update it. I also helpful and resolve this issue.
For Imporve the performance of ACT_UPG phase.
How to improve performance in ACT_UPG - ERP Upgrade
Regards,
majamil