After upgarde to PBA 5.x the PACI screen works incorrectly - it is possible that prices are not calculated or an attempt to place an order on any of the configurations chosen results in the error:
Some fields have erroneous data or need to be filled in.
In PA 5.5 the possibility to determine different resource limits for different OS templates was implemented (resource restrictions). The resource restictions are left empty after POA upgrade, which causes the issue described. The behaviour is a bug with id #PBA-53779.
The bug is to be fixed in PBA 5.5.4. Until an update is available it is required to fill in the resource restrictions for "CI Virtual Environments" resource types.